12 bolt Chevy or Ford 9
09-24-2002, 11:53 PM
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12 bolt Chevy or Ford 9
Ok... I'm collecting to many parts. Have a narrowed Chevy 12 bolt for my 87 Camaro, got the 4.56 gears, but need to get the axles cut and splined. Got a narrowed Ford 9 housing with matching Strange axles. Picking up another Ford nine complete axle hopefully this weekend, figuring I'll just use the pumpkin and not sure what gears are in it (but cheap to replace). Trying to figure which one to go with. Sugestions? Both will fit the 16x32 Goodyear slicks. Man I could have picked an easier hobby
Bob
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09-25-2002, 12:33 AM
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A correctly built 12 bolt will take more abuse than the credit it is not given. They both have pro's and con's. The only reason I would even consider a 9" is with something that makes 600 lbs and yanks the tires off the ground repeatedly.
09-25-2002, 07:06 AM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
How are you planning on installing either one into a third gen? Unless you have and aftermarket 12 bolt housing or the special bracket for the 9" there's no way to attach the torque arm.
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09-25-2002, 08:51 PM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
OK That clears that up.
As much as I would like a 12 bolt, I find the 9" easier for a race car. My current combination works perfect at my home track. If I travel to any other track I have to race at a lower elevation. I really discovered a problem when I went to Yakima. Here my shift light comes on right as I cross the finish line. In Yakima it was coming on at the 1000 foot mark. I had too much gear for the lower elevation and was running out of track. I have no more room for taller tires and I can't raise the shift point any higher.
Since the season is just about over I won't have to worry about traveling until 2003. With the 9" I just need to get another center section, spool and some 4.3x gears since my 4.56 gears are too steep for lower elevations. If I ever go to Mission and race at sea level I would probably only need 4.10 gears (never did the calculations yet).
With the 9" doing a gear swap for a situation like mine becomes real easy. Pull the axles, drop the driveshaft, drain the diff, swap the center section and reinstall everything. I could have it all changed in about 1/2 hour. You couldn't do that with a 12 bolt.
If you have lots of money to throw around you can have the best of both worlds and buy a special carrier and center section that lets you have 12 bolt gears in a 9" housing.
As much as I would like a 12 bolt, I find the 9" easier for a race car. My current combination works perfect at my home track. If I travel to any other track I have to race at a lower elevation. I really discovered a problem when I went to Yakima. Here my shift light comes on right as I cross the finish line. In Yakima it was coming on at the 1000 foot mark. I had too much gear for the lower elevation and was running out of track. I have no more room for taller tires and I can't raise the shift point any higher.
Since the season is just about over I won't have to worry about traveling until 2003. With the 9" I just need to get another center section, spool and some 4.3x gears since my 4.56 gears are too steep for lower elevations. If I ever go to Mission and race at sea level I would probably only need 4.10 gears (never did the calculations yet).
With the 9" doing a gear swap for a situation like mine becomes real easy. Pull the axles, drop the driveshaft, drain the diff, swap the center section and reinstall everything. I could have it all changed in about 1/2 hour. You couldn't do that with a 12 bolt.
If you have lots of money to throw around you can have the best of both worlds and buy a special carrier and center section that lets you have 12 bolt gears in a 9" housing.
09-25-2002, 10:40 PM
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Good idea about being able to swap the gears. but elevation isnt a problem in my area. Got me thinking though on the 4.56, I'm at 1000 feet. will depend on engine. Someday will get this bolted up and running.
Bob
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Always thought it is a beautiful country
09-25-2002, 11:06 PM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Not really that good. Altitude of the track is 3350 feet. Once this year we reached 7000 feet density altitude and a couple of weeks ago we hit 6000 feet. If the rain holds off this weekend we may actually be below 4000 feet for the last race of the season.
Your choice of 4.56 gears may not be a problem with 32x16 tires. I'm only running 29x9's. It's all going to depend on where your shift point is. I shift at 6800 but at lower elevations I was making more HP quicker. More HP means the engine is doing work quicker. When the rpms come up quicker, you shift quicker and run out of track. Look at it the other way also. A car that runs perfect at 1000 feet elevation comes here. Because they're making less hp, chances are they don't shift into high gear until well after the 1/8 mile. As they cross the finish line they're nowhere near their red line.
A week later when I was back home my first pass down the track felt like driving a big truck even though it was my quickest pass on the home track.
I always tell people that a 12 second street car here or in places like Denver is a very fast car. It's hard enough to just have a street car get into the local 100 mph club at the local street legal races at the track.
Your choice of 4.56 gears may not be a problem with 32x16 tires. I'm only running 29x9's. It's all going to depend on where your shift point is. I shift at 6800 but at lower elevations I was making more HP quicker. More HP means the engine is doing work quicker. When the rpms come up quicker, you shift quicker and run out of track. Look at it the other way also. A car that runs perfect at 1000 feet elevation comes here. Because they're making less hp, chances are they don't shift into high gear until well after the 1/8 mile. As they cross the finish line they're nowhere near their red line.
A week later when I was back home my first pass down the track felt like driving a big truck even though it was my quickest pass on the home track.
I always tell people that a 12 second street car here or in places like Denver is a very fast car. It's hard enough to just have a street car get into the local 100 mph club at the local street legal races at the track.
09-26-2002, 01:56 PM
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Car: 1986 camaro
Engine: 383 sbc
Transmission: th-400
Axle/Gears: 4th Gen 10 bolt/Detroit TrueTrac 4.
the 9" are tough and they have a quick change gear setup where as the chevy arent all that easy to change. that is one of the main reasons they are used in racing applications is the ease of installation with gears
09-26-2002, 08:36 PM
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Not to rain on the parade but...
Considering the cost and parts availablity for both; if you are going to build a rear end to handle any kind of real hp/tq and a chassis to hook it all up, you most likely are going to put some real axles into it in the first place. As for the axles themselves, yes you can choose to have a 'press on' style bearing in either a ball roller or tapered roller configuration for a 12 Bolt (one better for drag racing, one for road racing), from that point, yes you can have the axles cut and resplined. You can even have a spline count up to 35.
As for gear swaps, all you need to do is set up the pinion depth on whatever gearset you may changing when you have the diff apart for what ever reason and swap them in and out just as easy. Since you already have press-on axle bearings from the 'real' axles you have purchased it is all the same. And yes you can do all of this in a half an hour.
Just to let you know, I am not against a 9". There are just too many unknown factors in differential building that most do not know, and nobody gives the 12 Bolt any credit. 9's are great, but heavier and less efficient. Their strength lies in that the pinion does have a spigot and a bearing to support it. The only reason it needs this is that the pinion is so much further from the ring center line that it needs the support as not to break. The other nice thing about the overall design is that the third member is seperate from the axle tubes. When a car hooks up really hard, the tubes tend to bend forward, thus, changing not only the carrier bearing pre-load but it also changes the distance of the ring in relation to the pinion. Brace it correctly and that problem goes away.....
All in all, building overkill is lots-o-money. You can build a 12 Bolt for much less than a 9", and some applications dont really need that much money spent on a diff when it should of been or could be spent better else where. I have been building differentials for about 15 years. I have put 12 Bolts in 1200hp land speed record cars, 700hp road race cars, drag cars etc.... and they live. I have put 9's in the same things and they live as well, but damn it, its a ford part.
Considering the cost and parts availablity for both; if you are going to build a rear end to handle any kind of real hp/tq and a chassis to hook it all up, you most likely are going to put some real axles into it in the first place. As for the axles themselves, yes you can choose to have a 'press on' style bearing in either a ball roller or tapered roller configuration for a 12 Bolt (one better for drag racing, one for road racing), from that point, yes you can have the axles cut and resplined. You can even have a spline count up to 35.
As for gear swaps, all you need to do is set up the pinion depth on whatever gearset you may changing when you have the diff apart for what ever reason and swap them in and out just as easy. Since you already have press-on axle bearings from the 'real' axles you have purchased it is all the same. And yes you can do all of this in a half an hour.
Just to let you know, I am not against a 9". There are just too many unknown factors in differential building that most do not know, and nobody gives the 12 Bolt any credit. 9's are great, but heavier and less efficient. Their strength lies in that the pinion does have a spigot and a bearing to support it. The only reason it needs this is that the pinion is so much further from the ring center line that it needs the support as not to break. The other nice thing about the overall design is that the third member is seperate from the axle tubes. When a car hooks up really hard, the tubes tend to bend forward, thus, changing not only the carrier bearing pre-load but it also changes the distance of the ring in relation to the pinion. Brace it correctly and that problem goes away.....
All in all, building overkill is lots-o-money. You can build a 12 Bolt for much less than a 9", and some applications dont really need that much money spent on a diff when it should of been or could be spent better else where. I have been building differentials for about 15 years. I have put 12 Bolts in 1200hp land speed record cars, 700hp road race cars, drag cars etc.... and they live. I have put 9's in the same things and they live as well, but damn it, its a ford part.
Last edited by chacane67; 10-01-2002 at 12:45 AM.
09-26-2002, 10:57 PM
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Damn 'chacane67' I would love to hear your knowledge on the 10 bolt 7.5". What is it's main weakness...HELP me, help it survive 425FP on a road course.
I've heard that the 12 bolt doesn't get the credit. I had a good convasation with a guy about 9's & 12's, and I'm sold on 12's even though a lot of circle track guys run 9's...
BTW: I have that Auburn coming to my door in the morning with a Jegs support cover. I'll have to put that Eaton in a 12 bolt, if this sucker blows up!
Ron
I've heard that the 12 bolt doesn't get the credit. I had a good convasation with a guy about 9's & 12's, and I'm sold on 12's even though a lot of circle track guys run 9's...
BTW: I have that Auburn coming to my door in the morning with a Jegs support cover. I'll have to put that Eaton in a 12 bolt, if this sucker blows up!
Ron
Last edited by ronterry; 09-26-2002 at 11:00 PM.
09-27-2002, 12:15 AM
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Well chacane67... you seem to be the man on this. Leaning more to the 12 bolt. All I know of the 10 bolt 7.5 is its the weakest link in the whole drivetrain.
09-27-2002, 12:55 AM
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Well the venerable 7.5" does have it share of weakness. When considering what we are trying to do with the cars we drive, we are really two or three gears ahead of the manufactures.
Its main weekness is its size:sillylol: I would have to say I would start pointing fingers at the ring and pinion...... I mean a damn jetski impeller is bigger. Mechanically it all really comes down to the theroies of leverage and applied surface aera. When you start dropping gears into them, say 4.10's or greater, and you hook up hard.....just once.....and I can almost assure you that I can find root shear cracks forming from the 'toe' end of the pinion teeth. The funny thing is, this will happen just once, and you could drive for another couple of months before it blows a couple of teeth off the pinion. Basically there is not enough effective surface aera to transfer the mechanical energy, through the ring and pinion, that it really needs to have to put up with the power we can create. Why does a 9" or a 12 Bolt live? They have 9"/8.750" (respectivly) of ring gear, with the amount of surface aera that goes along with a gear of that size.
Next would be the axles. Although, throughout the years I have only replaced very few axles due to breakage or failure. Their faults lie within metallurgic problems. More to a surface hardness-depth variant. The axles just seem to come apart on the bearing surface (where the axle rides on the bearing).
And not to make this post too long, there is last but not least, the differential itself. It too is just too small. I mean come on, the whole rear end was designed for a four cylinder truck. Just pull the trigger and get it over with. But if you for some reason HAVE to run a 7.5, my choise would be the Eaton or a Thorsen/Gleeson (AKA Torsen). The Eaton you can tune and rebuild. The Thorsen you cant really rebuild persay, but if you want them to live you have to go through them and set up a tolerance or two on a few of the internal parts. The real nice thing about a Thorsen is it just adjusts itself for the direction youre going in. You can make a 7.5 live.....for a little while. On the circuit it was the only thing you could run, so we did what we could, and they held up ok. Lots of prep work though.....
If you have any questions, lets just run through one part at a time and I can give you a direction or two to accomplish a higher rate of surviveability. Its all pretty easy stuff, just time consuming.
Its main weekness is its size:sillylol: I would have to say I would start pointing fingers at the ring and pinion...... I mean a damn jetski impeller is bigger. Mechanically it all really comes down to the theroies of leverage and applied surface aera. When you start dropping gears into them, say 4.10's or greater, and you hook up hard.....just once.....and I can almost assure you that I can find root shear cracks forming from the 'toe' end of the pinion teeth. The funny thing is, this will happen just once, and you could drive for another couple of months before it blows a couple of teeth off the pinion. Basically there is not enough effective surface aera to transfer the mechanical energy, through the ring and pinion, that it really needs to have to put up with the power we can create. Why does a 9" or a 12 Bolt live? They have 9"/8.750" (respectivly) of ring gear, with the amount of surface aera that goes along with a gear of that size.
Next would be the axles. Although, throughout the years I have only replaced very few axles due to breakage or failure. Their faults lie within metallurgic problems. More to a surface hardness-depth variant. The axles just seem to come apart on the bearing surface (where the axle rides on the bearing).
And not to make this post too long, there is last but not least, the differential itself. It too is just too small. I mean come on, the whole rear end was designed for a four cylinder truck. Just pull the trigger and get it over with. But if you for some reason HAVE to run a 7.5, my choise would be the Eaton or a Thorsen/Gleeson (AKA Torsen). The Eaton you can tune and rebuild. The Thorsen you cant really rebuild persay, but if you want them to live you have to go through them and set up a tolerance or two on a few of the internal parts. The real nice thing about a Thorsen is it just adjusts itself for the direction youre going in. You can make a 7.5 live.....for a little while. On the circuit it was the only thing you could run, so we did what we could, and they held up ok. Lots of prep work though.....
If you have any questions, lets just run through one part at a time and I can give you a direction or two to accomplish a higher rate of surviveability. Its all pretty easy stuff, just time consuming.
Last edited by chacane67; 09-28-2002 at 12:16 AM.
09-28-2002, 11:06 PM
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Car: '94 Corvette
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------------------
Forgive me that this went off course from the original topic.
------------------
For what it's worth, I'm going to try to get the tolerances right on.
BL is working out good @ .008 (calling for .008), however when I had to change the pinion dept it added .002 to it.
PL is hell on earth. I'm using a solid spacer/shims, and I think I have it close. 2.0-2.5FP @ 125FP.
Tooth Contact, well you tell me (image below). The original shim was a .035". The first check was obvious, and after a crude dept check, I came up with 2.295+- (calling for 2.308). Broke out the bearing seperator, and replaced stock shim with .025 slim pack. My crude check was super close @ 2.305 -da-
.
That's about it today, however the stock carrier shims where way to tight, so I'm used Richmond shim pack. I guess the only way to check PL on the carrier, is by a final PL test on the yoke? It's tight right now, but not so tight that I need to hammer the crap out of the last shim. So I'm thinking thats ok?
Ron
Forgive me that this went off course from the original topic.
------------------
For what it's worth, I'm going to try to get the tolerances right on.
BL is working out good @ .008 (calling for .008), however when I had to change the pinion dept it added .002 to it.
PL is hell on earth. I'm using a solid spacer/shims, and I think I have it close. 2.0-2.5FP @ 125FP.
Tooth Contact, well you tell me (image below). The original shim was a .035". The first check was obvious, and after a crude dept check, I came up with 2.295+- (calling for 2.308). Broke out the bearing seperator, and replaced stock shim with .025 slim pack. My crude check was super close @ 2.305 -da-
.That's about it today, however the stock carrier shims where way to tight, so I'm used Richmond shim pack. I guess the only way to check PL on the carrier, is by a final PL test on the yoke? It's tight right now, but not so tight that I need to hammer the crap out of the last shim. So I'm thinking thats ok?
Ron
09-28-2002, 11:26 PM
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Car: '94 Corvette
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Transmission: 4L60E
Almost forgot, Auburn has a Differential Replacement Exchange Program ( D-REX 
)
It basicly allows you to replace/exchange your carrier for $85 bucks, within 4 years.
The Auburn carrier that I got the other day is a sealed unit. It would have to be machined open.
Ron
)It basicly allows you to replace/exchange your carrier for $85 bucks, within 4 years.
The Auburn carrier that I got the other day is a sealed unit. It would have to be machined open.
Ron
Last edited by ronterry; 09-29-2002 at 02:20 AM.
09-29-2002, 04:47 PM
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Well, thats a picture of the 'coast' side. I would be interested in seeing the 'drive' side of the ringgear. Coast is secondary.
Are you actually using a pinion depth checker?
Dont sweat the BL for now, 8-10 is fine.
Shoot a picture of the drive side.....
Are you actually using a pinion depth checker?
Dont sweat the BL for now, 8-10 is fine.
Shoot a picture of the drive side.....
09-29-2002, 05:00 PM
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Car: 87 IROC L98
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Axle/Gears: Ford 9"/31 spline spool/4.86
Trouble with setting the pinion depth with the shims is that they're behind the pressed on bearing. Any driveline shop that regularly sets up rear ends will have special pinion bearings. Buy a new bearing and have the center machined out a few thousands of an inch. Just enough so that the bearing will slide on by hand. Now if you need to change the shims the bearing will just fall off. Once the shim depth is figured out, the proper bearing is pressed on.
09-29-2002, 05:35 PM
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Another idea used is to put shims under the inner pinion bearing race itself. Then you wont have to pull the bearing on and off the pinion so many times if one were having trouble setting it up. But it only works if you need to add depth........
But there is a bearing seperator available from Reider Racing that makes it effortless.
Food for thought
But there is a bearing seperator available from Reider Racing that makes it effortless.
Food for thought
09-29-2002, 05:38 PM
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It's OK Stephen, I've got a 20ton shop press, and a bearing seperator. Those two tools, makes it no work at all, however that test bearing is a wonderfull idea, and I'm sure would save tons of time!!!
I should charge money around here to press bearing...
I'll head out, and see if I can get a pic of the drive side. I know last night I was getting a weak pattern on the drive side, but I'm assuming that's because I was using a wrench to turn the carrier. I guess counter clockwise if I was standing in front of the left wheel. Is this correct?
Ron
I should charge money around here to press bearing
...I'll head out, and see if I can get a pic of the drive side. I know last night I was getting a weak pattern on the drive side, but I'm assuming that's because I was using a wrench to turn the carrier. I guess counter clockwise if I was standing in front of the left wheel. Is this correct?
Ron
09-29-2002, 06:10 PM
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Almost forgot, the crude way I checked the pinion dept, is hmmm yes off the bearing surface with the end of a dial caliper, and straight edge. I know-I know, I'm not taking much merit to it's results.
Ron
off the bearing surface with the end of a dial caliper, and straight edge. I know-I know, I'm not taking much merit to it's results.Ron
09-30-2002, 12:24 AM
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hmmm here a shot of the pattern with a .030" pinion shim...
Call me crazy but it looks the same as the .025"... hmm the preload might be a little tighter though...Just thought of that, I did it by hand this time to about 2.5-3.0FP
BTW: the coast side looks the same as the above also.
Ron
Call me crazy but it looks the same as the .025"... hmm the preload might be a little tighter though...Just thought of that, I did it by hand this time to about 2.5-3.0FP
BTW: the coast side looks the same as the above also.
Ron
Last edited by ronterry; 09-30-2002 at 12:27 AM.
09-30-2002, 12:51 PM
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Ok, tell me a little about your parts. Specifically gear manufacturer.
Funny thing, different gear manufacturers products set up differently. My first impression is that the gear set is too deep. But depending on who's gearset it is will determine the way to go depth wise. Hopefully they are US Gear/Strange or Precision or for that matter, OE GM.
But anyway you look at it, right now and you are looking for a change of atleast 0.010".
Funny thing, different gear manufacturers products set up differently. My first impression is that the gear set is too deep. But depending on who's gearset it is will determine the way to go depth wise. Hopefully they are US Gear/Strange or Precision or for that matter, OE GM.
But anyway you look at it, right now and you are looking for a change of atleast 0.010".
09-30-2002, 07:45 PM
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Boy 'O' boy - pictures pictures pictures
I'm using a single .015" shim under the pinion, and BL = .009
More ???
Ron
I'm using a single .015" shim under the pinion, and BL = .009
More ???
Ron
Last edited by ronterry; 09-30-2002 at 10:14 PM.
10-01-2002, 12:32 AM
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Ugh, Richmonds rockwell out really, REALLY hard. So dont be dissapointed if you have some float or coast noise.
I just checked out your new pictures, and Richmonds like to be deep. I'll stab at around 0.042-0.047" depth with 8-10 lash. Lean on the 10 side for lash as to allow for more oil to cushion some if any noise.....
I'd try too shoot for 0.042" and 10 lash, cuz if you have to add 0.005" more depth, your backlash should be right on about 0.008".
-edit-
Oh yeah, try and wipe a pattern every third around the ring gear. It would be better to take the average of the three 'pictures' to ascertain what we need to see. Sometimes small measurements of run-out can give you a false average reading and then when you wipe the other side, there is the possibility of seeing something totally different.
I just checked out your new pictures, and Richmonds like to be deep. I'll stab at around 0.042-0.047" depth with 8-10 lash. Lean on the 10 side for lash as to allow for more oil to cushion some if any noise.....
I'd try too shoot for 0.042" and 10 lash, cuz if you have to add 0.005" more depth, your backlash should be right on about 0.008".
-edit-
Oh yeah, try and wipe a pattern every third around the ring gear. It would be better to take the average of the three 'pictures' to ascertain what we need to see. Sometimes small measurements of run-out can give you a false average reading and then when you wipe the other side, there is the possibility of seeing something totally different.
Last edited by chacane67; 10-01-2002 at 12:37 AM.
10-01-2002, 02:26 AM
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Ok, I slap a total of .045"s worth of shims or so under the pinion bearing, and see if it looks passable. - And around .010 on the BL.
I should of figured cause everything (carrier, gears, bearings) is new & aftermarket, and getting a text book pattern was going to be a trud.
Ron
I should of figured cause everything (carrier, gears, bearings) is new & aftermarket, and getting a text book pattern was going to be a trud.
Ron
10-01-2002, 02:32 AM
#37
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Ya know, close is close, but with the Richmonds I wouldnt take any chances. They are known for gear noise. So just take your time and dial it perfect. This is something I am sure you will thank yourself for later. Textbook on drive is your only concern!!!!
BTW, 3.42 is my favorite ratio, Good balance for both; quick but you can still cruze......
BTW, 3.42 is my favorite ratio, Good balance for both; quick but you can still cruze......
10-01-2002, 02:47 AM
#38
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Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
Cool, I get up some what early tomarrow, I will say around the crack of noon , and spend some time on that pattern.
I've got nothing but time, when it comes to making it perfect!
Ron
, and spend some time on that pattern. I've got nothing but time, when it comes to making it perfect!
Ron
10-01-2002, 04:52 PM
#39
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Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
Well 'chacane67' this is the pattern at .050 shims, BL=.009.
The gears are making a more of a ticking noise also?
Ron
The gears are making a more of a ticking noise also?
Ron
10-01-2002, 05:47 PM
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Car: 4
Engine: 6
Transmission: 5
To add to chacane's comment about taking patterns at more than one spot (a very good idea, IMHO almost mandatory): some people will "lap" the back side of a new ring gear on a thick piece of glass with 600 or so sandpaper, to make it sit flatter on the carrier and reduce the runout somewhat... the gears tend to warp somewhat during heat treating.
Definitely measure the backlash at multiple points too.
Definitely measure the backlash at multiple points too.
10-01-2002, 07:11 PM
#41
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Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
I don't know if this is a biggy, but I just noticed the ring & pinion have different serial numbers! The tooth count is correct for both, but it seem they may have been mixxed up with another 3.42 set. (I bought them through Summit Racing, so I can yell at them!)
I just can't that baster to dial in! I just tried .046, and it's the same with the one above.
Yea, I did try marking at 3 location, and checked the BL at three location, and the runout is non existing.
?????
Ron
I just can't that baster to dial in! I just tried .046, and it's the same with the one above.
Yea, I did try marking at 3 location, and checked the BL at three location, and the runout is non existing.
?????
Ron
10-01-2002, 07:29 PM
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Yup, I was leaning towards 0.042". And I just looked at my book of R/P swaps from over the years and the Richmond numbers are all about 0.038" to 0.042", with 85% of them at 0.042".
The ticking is either the pinion gear hitting the posi case or the pinion gear is way too deep and is binding off the tooth end.
The ticking is either the pinion gear hitting the posi case or the pinion gear is way too deep and is binding off the tooth end.
10-01-2002, 10:44 PM
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Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
OK, .042", and I'll gauge it at three different areas...and hopefully I'll get a go/no go from there, and work on the BL. This is work!!!
I guess the serial number must not be to much of biggy. (That's good)
Man 'chacane67' I appreciate you patience!!!!!!!!!!!!!!!!
I guess the serial number must not be to much of biggy. (That's good)
Man 'chacane67' I appreciate you patience!!!!!!!!!!!!!!!!
10-02-2002, 07:46 PM
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Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
Still a little bit of ticking, but not bad (I can get a video of it?). BL=.009 PD=.042
One question: Should I buy a depth gauge? Would this tool get me in the ball park? I've seen a Pro-Form for 100 bucks over at Jegs, and I need to check if summit sale one of there own.
Ron
One question: Should I buy a depth gauge? Would this tool get me in the ball park? I've seen a Pro-Form for 100 bucks over at Jegs, and I need to check if summit sale one of there own.
Ron
Last edited by ronterry; 10-02-2002 at 11:06 PM.
10-04-2002, 01:47 PM
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Car: No more birdy
Originally posted by ronterry
Here's a .036 BL.012
It doesn't tick either direction.
One I havn't tried...
Ron
Here's a .036 BL.012
It doesn't tick either direction.
One I havn't tried...
Ron
Drop 5 from the pinion shim "at a time" and it will move the pattern into the center of the ring gear.
10-04-2002, 08:34 PM
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What was the factory shim? Cuz its getting close.......knowing the factory might of helped.....
Diff work is a hands on thing and this computer thing is just messin it all up. Sometimes you have happy parts and sometimes you dont.
Diff work is a hands on thing and this computer thing is just messin it all up. Sometimes you have happy parts and sometimes you dont.