I have an 82 Vette which I recently had a rebuilt 700r4 installed. I let the car warm up for about 5 minutes and when I take off the car sometimes won't shift into second gear until about 2 miles or so. It seems once the car makes the shift and the trans warms up everything is fine, is this normal? This happend yesterday for the first time and it was about 60 degrees out. The trans has about 300 miles on it since the rebuild. I have not contacted the shop yet as I want to findout if anyone else has experienced this. The mechanic said to wait until 1,000 miles for proper breakin before I really get on it, does this seem right? I have also noticed that when I pin it in third, the car will downshift but it does not want to shift from 2nd to 3rd at 5000 rpms unless I let of the throttle, I let of the throttle because I do not want it to rev much higher than the 5000rpm redline. What would be a good shift point for this motor, it is 100% stock. I have not done a full throttle launch as I am waiting until I get 1000 miles on the trans to see what the 1st to 2nd shift point is. How high can these motors rev before I should be worried. Any reccomendations as to when I should change the fluid? The mechanic said 20,000 but I think this is a little high for a new trans. Sorry for the long first post.

Thanks,

Mike

Great site!

 

Adjust the TV cable and see what happens

 

 

mine was doing that this past winter/spring, brought it to trans shop. they removed the valve body and said that a plunger type valve was hanging up, causing the problem, now all is well

 

You think the rebuilder whould have had all that adjusted just right before he released it to you!
I had mine done this summer and it shifts better than it ever did. Will shift at 5500 rpm only at wide open throttle. With nice firm shifts.
I would have him do it right, waiting till 1000 miles is not going to change that. You don't want to be driving around in first gear like that.
Good luck with it.

 

rebuilder can't adjust the TV cable, it's connected to the throttle linkage and needs to be adjusted in the car

 

The 700r4 trans is very finicky about valve body torque. I think the manual calls for 8-12 foot pounds with a low number around the TV valve. If it's overtorqued, the shift valves can and will stick.

Did your rebuilder install any type of shift improver? I used one made by Superior that I got from a local parts house. Had to do a minor bit of machine work to the servo, but it worked great. I put one in a 72 Chevelle I built, and built several for other guys. I know one in particular had a 98 Camaro he did a bit of Autocross/road race stuff with and really liked it..


Other than that, it sounds like a valve or two is sticking. I'd get a pan gasket/filter, a set of valve body gaskets, a book from a trans parts supplier, drop the valve body and start looking. Watch the check *****.

 

I had a similar problem. I called it hanging. Mine was fuel pump related...not enough psi. changed to an 85 pump and it solved the problem.

Jim

 

my tranny is quirky as well. ive taken alot of weirdness out of it by hooking up a switch to engage lock out when desired. sometimes it wont go into 4th gear unless the switch is on. somtimes it is in 4th before 45mph which the motor doesnt like. most of the time it hits 2nd gear way too early especially at the track where id want to bring it to 6700. adjusting the tv cable is the first place to start and be patient tiny little adjustments at a time.

 

Thanks for the advice guys. I am not sure if any type of shift improver was added as the mechanic sent the car somewhere else to have the trans done and he wasn't to specific as to what was done to the trans besides saying that it has better clutches and bands. Initially I was going to purchase a raptor 700 stage two and install it myself or have my local shop do it but he said he wouldn't warranty the work so I had him rebuild the transmission since he gave a 12 month 12,000 mile warranty. I am going to see him tomorrow as he installed a new radiator and I just noticed that the electric fan is to close to the radiator and has caused it to leak. I'll let you guys know how it goes. I wish I could do this stuff myself as it is hard to find a good mechanic.

 

I heard back from the shop the other day and the guy said that the person who rebuilt the trans received a batch of defective governors which would spin on the shaft until they are warmed up and than they would be fine. He said the governors were replaced and everything is fine now. I am picking up the car Saturday and I am keeping my fingers crossed. Instead of replacing the radiator he is having the radiator welded and said I won't even notice it. Apparently a bushing was bad in the electric fan which caused it to rub against the radiator. Hopefully everything will be back to normal and than I can try to get some more power out of the motor. Are there any small things I can do to waken the motor up, it is completly stock. An exhaust is the first thing on my list. Is it possibly to get 300hp out of the motor with an exhaust and some modifications to the cross-fire, I would rather not install a cam and I am not looking to make a firebreathing drag car, just a street car with a little more power.

Thanks

 

My 85 Pickup did that from the time I brought it home from the dealer until 14 years later when I gave it away with over 165,000 miles on it. Only when it was real cold out though.

 

Thanks Redwing. Mine was happening when it was 60 degrees outside. I pick it up tomorrow and I am hoping everything is right this time.

 

Send a PM to CF member PeteK (C4 guy) with a link to this thread, he knows 700r4s inside and out.

 

I finally picked up the car on Saturday and gave it a good shakedown. It shifts way better than previously and seems to shift at about 5000 when pinned from a dead stop with a nice firm shift. What I did notice is when I have it in od it shifts into 4th way to early, sometimes when you are going about 45 or so and the revs drop to about a grand, does not seem happy there. By keeping it in third it avoids this problem. When you get on it in third sometimes, depending on your speed, it downshifts twice and really gets up and goes. One other thing I noticed is it is reluctant to downshift to second from 4th when you get into it. I need to drive it a little bit more and I will post my results. Star thanks for the advice as I will keep Petek in mind if I plan on adjusting the TV cable to get better downshifts from 4th.

 

82V, you post there at 619pm is about the way my 700 reacted with 336 gears....and frankly I hated it....not only that, but the thing would downshift at 70mph wind hell outta the engine and not upshift untill hell froze over...ie...I lifted.....

my 200 4r here now, will not downshift at 70-80 or so, and just pulls hard....all locked up and tight....the upshifts are FAR superior....
but some of that is gear ratios....

IMO they made some really bad decisions on gearsets for the inherant 700 design....3.xx first to 1.8 second to 1.0 third to .7 o/d is just silly...

vs the 200 at 2.5, 1.6?, 1.0, .68 o/d.......

with a TQ Conv I see no reason to ever have a 1st gear heavier than 2.5x in any normal CAR....it's not a diesel truck with 10 grand on it's tail....

 

I thought the ratios in a 700R4 were 3.06, 1.63 (not 1.8? ), and 1:1, with .7:1 OD:
try THOSE gear-spilts with 2.87s in the hills of Pennsylvania.....


Either-way, I agree that the 200-4R gearing is more in-line with the earlier THM350s and THM400s.

 

Glen, I beleive you are correct. Supposedly when the trans was built the guy changed the gears, I will findout if this is true and what the ratios are if he changed them. The trans was not done at the shop where I brought the car, they had someone else do it and I do not know exactly what components were put in the trans. I am fairly new to this and learning everyday. I will try to inquire as to what components are in the trans. The car used to be my Dad's but he passed away about 12 years ago and it has mostly sat in my Mom's garage for the past 12 years. It probably saw about 200 miles a year until the past three years when it just sat. A new Idler bar, front brake calipers, Radiator and rebuilt trans and the car is finally starting to come together, I can't wait until I have it dialed in. I didn't realize how much fun the car is to drive until recently as I used to either ride my dirtbike or streetbike and the Vette was a distant third. After selling my streetbike 4 years ago and driving the Vette the past two months I am hooked and want to get it setup properly. I now drive on the same roads I used to take my rice rocket and I am having a blast.

 

Glen, I beleive you are correct. Supposedly when the trans was built the guy changed the gears, I will findout if this is true and what the ratios are if he changed them. The trans was not done at the shop where I brought the car, they had someone else do it and I do not know exactly what components were put in the trans. I am fairly new to this and learning everyday. I will try to inquire as to what components are in the trans. The car used to be my Dad's but he passed away about 12 years ago and it has mostly sat in my Mom's garage for the past 12 years. It probably saw about 200 miles a year until the past three years when it just sat. A new Idler bar, front brake calipers, Radiator and rebuilt trans and the car is finally starting to come together, I can't wait until I have it dialed in. I didn't realize how much fun the car is to drive until recently as I used to either ride my dirtbike or streetbike and the Vette was a distant third. After selling my streetbike 4 years ago and driving the Vette the past two months I am hooked and want to get it setup properly. I now drive on the same roads I used to take my rice rocket and I am having a blast, albeit at much slower speeds.

 

Sorry for the duplicate posts.