Hi all! OK, I need some help/advice on my transmission. I recently put a B&M shift improver kit in my 700-r4 and now, after about 50 miles, third and fourth gear dont seem to want work. First, second and reverse still work great! I know that it is shifting in to 3rd and fourth cause I can feel it, and fourth actually powers the car a bit. I guess the best way to describe it is that it shifts, but is not responsive to the throttle in third and fourth. The trans is the original and has apx. 150k miles but has been behind a sbc crate motor with about 380hp for about 30k miles. My thought is that the trans is bad and needs to be rebuilt or replaced but I figured I would get a few opinions from some with more experience. Thanks!!!
-Jon

 

did you put the shift kit into the tranny in the hopes it would fix the slipping?

 

Well, before i put the shift kit in, it was really sloppy with the shifting. It would like shift sort of late under hard acceleration and 2nd to 3rd was pretty soft and 3rd to 4th was REALLY soft. It was like that when i bought the car but had recently gotten a bit worse. I installed the shift improver kit in hopes of firming the shifts up and making for a quicker 0-60 (which btw it did for the first 50 miles). I set the tv cable to what i think is the best position after quite a few test drives so i dont think the tv cable is the issue. Could it be posible that the shift improver made an existing problem worse or simply speeded up the death of my trans? Thanks!

 

Well, I surely hope not! I have a stage 2 B&M valve body (improver kit) for my ride but my trans acts fine. With it being cold and only driving it twice a month right now maybe it's the trans fluid not heating up as fast and making my shifting abit more later/rougher but I sure hope not because I'm planning on installing this into my trans valve body.

 

I would say your tranny needs a rebuild. Same thing happen to me a year ago. I went with a transgo kit. find yourself a good performace trans shop or do it yourself.

 

it's tough to say from behind a computer. What I have learned to call slipping might be what you call "soft"; who knows?

Anyway, when a tranny starts to go, some folks will go buy a shift kit in the hopes it will fix the real problem. Others will change the fluid and filter also denying reality.

Losing 3rd and 4th is a common failure in the 700r4 as well as 4l60(e)

If you continue to drive it, your fluid will eventually burn and you'll cause more damage.

In fact, I pulled a running engine and trany from the 3rd gen that I'm restoring. In addition to having the engine rebuilt, I also had the tranny rebuilt. No, it wasn't slipping and it shifted fine but I knew that it would eventually suffer the dreaded loss of 3rd/4th that I had a rebuild kit put in as well as a new forward sprag and boost valve. It had a lot of miles on the tranny and I don't like playing Russian Roullette.

 

Well, i have a friend with a 92 camaro and I helped him install the same kit and he has driven it over 5k miles trouble free.

 

Its def. slipping! I can sort of feel it go into 3rd and fourth, but when i press the gas, the rpms climb with no response with regards to acceleration.

 

How hard was the install? The only part about it that I dislike is the fact that the fluid has to be drained out to do the valve body kit.

 

Hahaha... Yeah, it got pretty messy! Just be sure to have a bunch of rags and/or sheets of cardboard. As far as "hard"... It really wasnt that complicated. The instructions are really pretty clear. You can probably do it yourself, but the valve body gets sort of heavy and it is hard to put the bolts back in with one hand. It is sooo much easier with another person! Oh, and if you dont have the retainer clip pliers... Go buy em or borrow em!!! I spent like 40 min trying to get the new retainer clip in just using a screwdriver. I finally had to borrow a pair of pliers from a friend... got it done in 2 min after that It took about 6-8 hrs the first time i did it, but if you know what you are doing it shouldnt take but 4 or so.

 

get quotes on rebuilds. If you can drop it yourself you'll save a lot because then it just becomes a bench job. Now might be the time to replace the TC if you were considering going to a higher stall. Otherwise, get a rebuilt one for about $80-$90. Your local tranny shop could provide one.

You may get away with just a rebuild kit. With high mile trannys I have the forward sprag replaced.

If you get quotes of over $700 for a rebuild that is just a bench job, keep shopping. If they will include "the beast" sunshell as well as new sprags then that's not bad.

good luck, and don't forget to add a couple quarts into the TC before re-installing it and do the ole lift and push so it seats all the way in.

 

Yeah, I think that is the route I will attempt. I was considering just swapping it for another used trans, but i dont really like the idea of putting a used trans in and having it blow a few months down the road. Thanks for all of your help!

 

You can't wish wear back in