So I had a really interesting day. Trying to install a shift kit on my newly acquired 1997 Bonneville. Well I thought I had a 4T65E as it seems to say everywhere. Got a shift kit for it, like I have installed in my other 2 GM cars of the same age range. Everything underneath seemed to look the same, accumulator looked the same. Well, I take it apart and swapped the springs as I did on my other cars. I go to install the spacers that come with it that go on the piston stem and they don't fit. Kind of dumbfounded because I did do this with no issue on the other cars, same kit. I installed the springs and left out to spacers figuring I would get back to it when I get it figured out. Now after doing some research, it seems the car may have a 4T60E, not that it seems to belong there but it is. Build date is late 96 but it is a 97 model. Anyone with any experience with these trannys know if it is safe to continue with the firmer springs? Not sure what to do at this point aside from taking it apart and putting the old stuff back. Would be a huge waste of expensive fluid. I will say it does shift much better than it did, just don't want to kill it if the firmer springs will hurt anything internally. Haven't taken it out too far to see if it softens up after it gets very hot. The battery was disconnected to allow for clearing the shift firmness memory. Thanks in advance for any info. I am sure many of you have had these apart at some point.
Shift kit install 4T60E/4T65E
- Thread starter 71Chevyguy
- Start date
Get the tag info off the unit.
You have a 4T60E not a 4T65E.....The Vacuum Modulator is a dead give away.
Correct kit for your unit is TransGo SK 4T60E-JR & Accumulator Piston kit TransGo 4T60-ACM2.
Reuse the original Accumulator Springs......If they are broken, Post the colors & I'll help with part numbers.
Line pressure is controlled by the Vacuum Modulator so disconnecting the battery has no effect on unit operation.
Correct kit for your unit is TransGo SK 4T60E-JR & Accumulator Piston kit TransGo 4T60-ACM2.
Reuse the original Accumulator Springs......If they are broken, Post the colors & I'll help with part numbers.
Line pressure is controlled by the Vacuum Modulator so disconnecting the battery has no effect on unit operation.
Yes it does have the modulator. I guess I will have to drop it all again and put the old springs back. I did drive it and it does shift well. But I don't want to mess anything up long term, so I will have to put it back to stock. They look the same from below and in the pan. Should have noticed that the side cover was different. The springs weren't broken, just trying to firm up the shifts a bit to help longevity. I guess I will have to get a new modulator and see if that helps any. I guess I can just look at it as an additional drain and fill. I drained and filled it twice before this, the fluid was nasty. Brown on the dipstick and just about black coming out with a suction gun. Interestingly enough, nothing in the pan aside from the magnet having its usual mess on it. Thank you everyone for the help, such a noobie mistake for someone who has been around the block more than a few times. Teaches me to pay more attention to details next time.
Originally Posted by eljefino
^ that said I made a 4t60 (non E?) in a 92 cutlass ciera happy with a "red stripe" modulator that allowed me to crank the screw down to my liking. And I didn't even have to drop the pan.
In the industry we call those a 440-T4 as they were designated before GM stopped using Hydramatic designations in 1987.
440-T4/4T60.....
The PCM controls TCC.
The TV Valve via the TV Cable controls the Shift Valve pressure that opposes Governor pressure.....(Shift Timing)
The Modulator Valve controls Line Pressure.
4T60E.....
The PCM controls Shift Timing & TCC
The Modulator Valve controls Line Pressure.
4T65E....
The PCM controls Shift Timing, TCC, & Line Pressure.
^ that said I made a 4t60 (non E?) in a 92 cutlass ciera happy with a "red stripe" modulator that allowed me to crank the screw down to my liking. And I didn't even have to drop the pan.
In the industry we call those a 440-T4 as they were designated before GM stopped using Hydramatic designations in 1987.
440-T4/4T60.....
The PCM controls TCC.
The TV Valve via the TV Cable controls the Shift Valve pressure that opposes Governor pressure.....(Shift Timing)
The Modulator Valve controls Line Pressure.
4T60E.....
The PCM controls Shift Timing & TCC
The Modulator Valve controls Line Pressure.
4T65E....
The PCM controls Shift Timing, TCC, & Line Pressure.
Looks like I have the 4CMW accumulator setup from pics and charts I found online. The accumulator itself externally looks identical to my 98 4T65e but inside the piston and spring configuration is a bit different. I have found some say to find firmer springs or make sleeves to limit piston travel like in the kit for the 4T65e. Basically what I achieved by using the firmer double springs instead of the stock ones. Decisions,decisions hahaha.
Hi I'm Brand new to the site! I have a problem along the same lines. i have a 1998 venture van that had a broken 1-2 accumulator spring. Pulled it apart and easily found that out. That was 4 months ago. It's been apart until today when the new spring finally showed up. Problem is I cant remember what way the spring and piston were situated. I picked up a 4t60e jr shift kit and accumulator kit. The broadcast code is no help so far, 61 8YAW W4FY2. I Also dont know if the accumulator piston cylinders should be filled with atf before i install it into transmission. Any help to keep my ol van rolling down the road would be greatly appreciated!!!! BTW love reading all the posts on this forum lots of great info!!
Lube the Accumulator Seals with ATF or TransJel, No need to fill the Accumulators.
Accumulator set-up can vary from model to model, But here's a diagram for a '98 Venture......
Accumulator set-up can vary from model to model, But here's a diagram for a '98 Venture......
Thanks for the help. I'm still not out of the water yet. Reinstalled all the parts, new spring new pistons new pins. Added 5 liters of atf to start with. And it barely moves. Have to rev to the moon to get it to move in any gear. What does it sound like I have done wrong? Thanks for any help anyone can offer!
Double check the fluid level, The converter would have drained down quite a bit in 4 months time.
