GreekItalianMan

Hi, just to say i beat a 3rd bmw today.Background is 12,000 original miles. garaged for 25 yrs. wasn't started for 13 yrs. I got it started and took the legacy over. But, the problem i'm having is, When i pulled into my car port. I went from park to reverse and it made a clunking sound(my dad pointed it out) then my dad got in(was originally his car). He kept shifting and after a while it stopped. But, he said it might be a bad u-joint,torque converter driveshaft. Do you guys know exactly what the problem is? Thank you for your time.

jakemussman

iTrader: (3)

Could also be too much backlash in the differential.

james.gould150

sounds an aweful lot like a u-joint but the sound would not just "go away" so try replacing trans filter/fluids and chck to make sure you have grease fittings along the shaft or at the u-joints if so grease em up ... may not solve your problem buut for a car that sat that long,it certainly wont hurt

GreekItalianMan

I don't usually hear it when i'm flooring it or driving normally. Only started hearing it today. I don't have jacks on hand, but i have these ramps to roll my car on. WHat kind of tools and grease do i need. Plus,if i have to change the trans filter how would i do that? I'm rather new at this.

james.gould150

grease , use a quality overthe shelf product(just go to a parts store and ask and get a grease gun obviously the nipples on the shfts are pretty universal...the trans if you are a newcomer,id recommend taking it to a shop its cheap...but if you do it yourself...1.) determine what trans you have (most likely 700r4) and get filter and gasket at parts store,2.) pulls your car up on jacks and get ready to get oily and dirty, 3) loosen all bolts on pan(dont take any out just loosen them)4.) loosen bolts towards the rear more than the front and let the oil drain until it stops pouring out 5) one hand holding pan even remove all bolts holding pan 6.) drop pan and your filter is right there , allow the rest of the fluid to drain into drain pan (shouldnt be much) 7) remove old filter,and inset new one opposite of removal 8.)put it back together with new gasket AND BE SURE TO REFILL TRANSMISSION WITH PROPER AMOUNT AND PROPER FLUIDS THIS IS VERY IMPORTANT A MANUAL WILL TELL YOU WHAT TO USE AND APPROX. HOW MUCH i know this is vague but it will give you a general idea of how to do it...if its your first time have someone who knows a lil about it and kind of go over your work (not an insult just transmissions are s.o.b's when something is slightly out) or take it to a shop to go over it when your done good luck (a manual will also give you better instructions than mine haha im at work typing this but its is proper)

hellz_wings

iTrader: (2)

The problem is that you have a 86 700R4 transmission. I installed a 3" aluminum driveshaft (new), ujoints+yoke, rebuild the tranny, torque convertor, torque arm, etc.. Basically everything you can think of in the driveline. I still get this thump when going in R or D. Why? After some research it appears that this was a problem in 1985 and 1986 700R4 trannies that GM fixed in 1987.. Go figure.. Try the above recommendations cuz maybe yours might be another problem, but I have changed everything and believe me, it still clunks the clunk lol..

GreekItalianMan

I might have to take it to a shop the first time. The mechanic is my dads friend there. I'll watch him do the work so i'll know next time. The problem is my dad has a herniated disc in his back so he can't go under the car anymore like he used to,and i'm not experienced enough to do the work myself. And hellz_wings my dad said the thumping noise is normal. It happens all the time for me too. The car shifts positions too when i do it.(Literally moves a bit when i shift from park to drive) does your guys cars do this too? I have the thm700r4 transmission

hellz_wings

iTrader: (2)

Yeah as I posted earlier, it was something that GM changed in the 700R4 transmissions in the year 1987, so your year 1986 (like mine) 'suffers' from this loud thumping. I literally replaced every piece including rebuilding the tranny and well it still does that. The only thing to cure that is to literally buy a 1987 and up 700R4 (not an option for me cuz i just spent 2k rebuilding mine). If your tranny breaks then you have an excuse to find a more recent version of the 700R4. 1987 to 1989 should work fine for our cars, maybe later years but i'm not 100% sure if they are exactly the same.

InfernalVortex

iTrader: (4)

If the car lurches from P to D then I would guess your rear brakes arent working so well. Could be some or all of the problem.

GreekItalianMan

It doesn't move anywhere just like shakes when shifting. Is that thumping damaging to the transmission? I would hate to have a 12k mile transmission die on me. Everything is stock on the car. It's like it's fresh out of a time machine. I'm pretty sure its the u joint. It's that clunking metal to metal sound that you can make by hitting two pipes together sort of. If it wasn't raining like a whoremonger i would bring it in. You replaced all of the parts and it still did it!? Is it the gears for the 86 R4 or is it a defect?

hellz_wings

iTrader: (2)

I don't know but I changed ujoints and yoke, rebuilt the tranny, and i also put a new eaton posi with new 3.73 motive gears in the rear and still does it lol.. I changed rear brakes too.. Man.. everything lol.. It still does it but screw it I have learned to live with it.. If you have an 86 I think all 86's have this problem.

GreekItalianMan

Yeah, i have an 86. As long as it doesn't damage anything. It can make an earthquake and i wont mind. I can't believe you did all that work and it never fixed the problem. What else have you done to your car?

hellz_wings

iTrader: (2)

It's all in the sig -->

GreekItalianMan

Nice, you did quite a bit on your car. Why does it say fwhp? Front wheel? or fly wheel?

Kevman

Mine clunks into reverse, and chirps the tires when I put it in drive, I just think it's cool..

GreekItalianMan

chirps in drive? the car moves?

hellz_wings

iTrader: (2)

Ah it's flywheel horsepower.. The dyno calculated wheel HP, so the guy did the math to tell me what I was at for flywheel.. But that was years ago, 2008 may actually.. It's definitely higher now after many more mods and tuning (i hope lol).

GreekItalianMan

Probably over 300 hp now. Where do you have peak torque? Stock rpm range?



This site should have a chatroom or something to make the conversations flow faster.

hellz_wings

iTrader: (2)

I don't think the engine makes 300HP, although after i upgrade the injectors to 22lbs ones and the fuel pump, then it might I hope!

My peak torque back then was at 3000RPM and peak horsepower was at 4800RPM but I think it should make power up higher now since I made a few more mods to the TPI as well as tuning.. I feel power up to 5000RPM it seems when I'm racing at the strip, but I won't claim it's that high till I dyno it for sure lol.. It has ported plenum, AS&M runners, Accel manifold, ported polished heads, bigger cam (don't know which one the previous owner put in .. darn!) and forged bottom end (also bored 0.030)

ASE doc

Driveline "rap" as it's generally known is most always caused by too high idle speed. Those who report that their car lurches when they shift from drive to reverse definitely have their idle set too high. Another common cause of "clunking" is a broken rear transmission mount.

hellz_wings

iTrader: (2)

My car idles very smooth at 750RPM, never surges, and is tuned that way, but you are right I have idled lower in the past although not where the engine wants to be, but around 650RPM and it clunked less, but the problem with that is not the high RPM revving, the clunk shouldn't be there in the first place.

What do you mean by 'rear' transmission mount? I have replaced my transmission mount with a prothane polyurethane one but it used to do it with a rubber one as well.

ASE doc

That's the mount I was talking about. You can check your rear axle for excessive pinion lash. But most every car I've evr checked for driveline rap was idling too fast. You do have a good point on the early 700R4 though. There may be nothing you can do on that, short of updating the trans. Oh, be sure to check both the bolts attaching the torque arm to the rear diff and the torque arm mount at the trans.

GreekItalianMan

Problem is, the car was sitting for a long time. I was too young to keep checking on the car. I have no idea what's going to go bad next. I don't have jacks or a lift. I can barely get underneath the car. There's surface rust because some douche decided to walk on my dads garage roof and his foot went thru it,causing moisture to get in. Plus he damaged my hood and fender when the wood fell. Idiot. Anyway, i'm pretty sure it's a u joint and not a mount. But, anything is possible. I'm expecting a lot of **** to break because of the sitting for 13 years. Hellz_wingz, how were the AS&M runners? Did they make a big diff? I'm thinking of getting tpis long tube runners

hellz_wings

iTrader: (2)

Hard to say as i installed everything at once.. But everything at once definitely made a nice boost but NOTHING i've done compares to the 2.73 open to 3.73 posi gear swap. You definitely feel it mid range to top (wish i would have dyno'd before and after but I only did after).

Best mods ive done aside from that are:
-LS1 front brakes
-Subframe connectors
-Rebuilding tranny
-New high performance tires

GreekItalianMan

That's pretty awesome. You didn't have the stock 3.27 from the factory? The SFC's must make a big difference. No more fish tailing? You put a lot of time and money into your car. What I don't understand is why our cars are valued at such a low price range, and that everyone ***** on them saying they can't race. If you don't mind me asking, how much money did you put into SFCS, runners, and for the ported heads what ration did you do Bore/stroke, stroke/bore. Sorry for the bombardment of questions. Newbie to the car stuff.

GreekItalianMan

okay, this is just weird, after my dad did that thing on monday. I started her up today and gunned her from the second i left my car port. The car doesn't do the clunking anymore and it shifts better than before. wtf? Is it possible that the u joints can get stuck? or something else?

hellz_wings

iTrader: (2)

No my car came with the garbage open 2.73 diff.. Nasty.. lol.. One wheel burnouts were embarrassing lol.. Well, the fish tailing stopped when I put new tires on to be honest.. What helped along the way were the SFC's, the spohn del sphere bushings out back, and the posi.. All these things made the rear alot more predictable in turns, even at high speed.. Ex: Did a crazy turn at 120KM/H last night (cold.. -4 degrees celsius weather in Montreal) and the car DID fish tail slightly because I gunned it through the corner but easily regained control when counter-steering and did it quite smoothly actually.. It's pretty much the combination of everything that helps not just one single part.

hellz_wings

iTrader: (2)

When I start the car in the morning and just leave before it gets fully warm, it doesn't clunk as bad.. Now, warm up your car, drive it around a good 10-15 mins, then put the car in park somewhere.. Then just put it in drive and it should clunk 'beautifully' like it did before.

Vader

As hellz_wings pointed out, the TH700-R4 built until late 1986 has this issue. Late 1986 model year and subsequent years included a 10-vane pump and an anti-abuse valve (in the secondary valve body) which cushions the engagement. Your trans could be updated, and it would be good to verify the correct curb idle RPM at temperature.

itsMikey

had the same noise ad realized my torque converter was loose

GreekItalianMan

I see hellz. That must've been really embarrassing. Yeah, true, a lot of parts work in conjunction with one another. Vader:Curb idle is when you pull over and check? My idle is usually 700-800. It's a smooth idle. I'll try running it for 15 today. But,the strange thing is it stopped the other day, I didn't hear it at all. I'm not going to lie, i floor my car every chance i get from a stoplight to 3rd gear in the street. Plus, how would i update my tranny? Swap it for a newer 700r4?

GreekItalianMan

Okay, well yesterday, i rode the car for about an hr. Got back and no clunking sound. She's more moody than a woman during her period. I give up. I don't know what the cause was, or why it stopped.

hellz_wings

iTrader: (2)

Wow.. That's good to hear! I am a bit baffled as to how come it stopped more-so than what causes it..

cuisinartvette

If the car has been sitting that many years treat the rearend and trans to some fresh fluid but I HIGHLY doubt theres anything wrong with it.
You got no miles on it, no reason to start fixing stuff that aint broke.

Worst case scenario you could have some Ujoints where the grease has dried up so to speak, lube them.

Lots of auto cars can do that, some all the time, some of the time or never.

When you go to put it in D or R and you get a firm umph feeling thats the trans telling you its healthy.

Go drive that thing.

GreekItalianMan

Thanks Hellz_Wingz and everyone else who helped. I guess your right Cusinartvette. I put about 357 miles on it since i got it started, i'm at 12,858. When something goes wrong on the car, it'll bother me for days on end until i fix it. Random questions but do you guys go to the bandit run every spring?