I had my rear end rebuilt and had 3.73 and posi put in. I got the speedo corrected but the shift points are way off. It jumps into 3rd at about 10 - 15mph which obviously isn't good. It feels like it's slipping but at that low speed, that might be normal. Once I get up to speed in 3rd, it's all good. Nothing slips and it just goes. What do I need to change or check to correct this? The trans was fine before the rear fix. Any ideas? I have seen a lot on govenor gears or something but not sure that's the correct answer. I'd like to hear from someone that has gone with a 3.73 and 700r4 combo or those who know about it.

Thanks to all who look.

 

Well i wont be too much help on this....


But obviously when you jump up to a steep gear like the 3.73's the tranny is going to be upshifting alot sooner because the driveshaft has to spin faster to do the same speed. But, unless they did some tinkering on the tranny the shift points will all be at the same RPM as before, just that the actual speed of the car has decresed when it upshifts.

As for the 'slip' at low speed, depending the rpm range its sitting at when you feel this, i would just say its the torque converter.

 

Try adjusting the TV cable.....

 

My TV cable is fine. Just watched Seinfeld!

Haha... kidding of course. Does this sound like a tv adjustment problem or is that a guess? I don't want to mess with things that are uncertain.

 

i put 4:10s in my transam,had 2:73s with 700r4 ,mine is in od. by 35 mph. been running it like this over 2 yrs. no probs .this is at light throttle ,the more you accelerate the further they are apart.lots of times ill just manual shift if its on a hill or in a hard pull.(gets the rpms up really quick) do wish i had gone with 3:73s tho.car is a blast to drive, love it when they pull up beside and you stomp it,it jumps back to first ,revs to 6k in like 2 secs.then second and drive .(look on face is worth a million dollars) then put it in od and cruise home @ 18 mpg,gotta love od.later jimmy

 

Glad to know it's not just me then. The problem I have with putting it in OD is that is sounds and feels like it's trying but not going anywhere. I have to manually shift from second to third... for some reason my shifter won't go down into 1st. It's a b&m megashifter... anyone know about that? Quite a bit of drive line noise. Other than that, the 1-2 shift is very mushy (getting worse) and the 2-3 shift happens about .021 seconds after that... (not real time, just seems instant) I wouldn't mind the fast shifting as long as it acted like it should with a shift kit. It used to shift so hard my dash mat would fly off. Rebuild? And if so, is it possible (i don't know squat about trannys) can it be built to better suit the 3.73 rear?

Thanks for the reply!

 

Ok, so I adjusted the TV cable a few times and it feels like the shift points are where they should be, or at least better than before. The shifts are still mushy. I'm thinking I've already damaged the trans and is why the shifts are slipping? Once in gear, the only time it will slip is when I floor it to downshift.

 

The TV cable is now adjusted correctly? How many miles are on the transmission? If you're having slippage, might want to get that checked out first...

You can modify the shift points by replacing the weights & springs in the transmission's governor. Since you changed gears, you might look into that option. The recalibration kits run about $30-$50 bucks (depending on brand) from Jegs or Summit.

It may take a couple of try's, installing and swapping springs and weights, to get the shift points where you want the gear changes to occur. Maybe you'll get lucky the first try.

Good luck

 

As for not getting first gear on the shifter...

Did you read the manual and pull out the pin that allows it to shift all 4 gears instead of just the 3 it comes preset at?

 

I thought my tranny was going out untill I did the TV cable, made a HUGE difference as far as shift points, and firmness.....good luck.....