4L70E, Russ K

[brantsz]

I was wondering if you could perform some of your tricks on this stock tranny tune. I have tried various tweaks off and on with not much luck. This is for a 08 Silverado vortec Max.

[Russ K]

You need to install the Corvette servo first. This is the only way to eliminate the WOT 1-2 slip shift.

Russ Kemp

[brantsz]

I agree, just really hate to swap tranny parts on a truck with 5k on it. Can I just set the TCC tables to 90 and 100 and call it a day, or will I have to change multiple settings for this to work correctly?

[Atomic]

The servo is a very easy job to do. It takes all of 20 minutes with basic hand tools.

[brantsz]

Can you help me with a part number or where I can buy the servo? I see tons of info on this for the 4l60e. I want to make sure that I order the right part for the 4L70E.

[Sneakyws6]

Same part for the:

700R4
4L60
4L60E
4L65E
4L70E

One of the first mods I did in my 2008 TBSS along with a better cooler (PCMforless) and a tranny reprogram with Russ's help. You will need the:

2nd gear apply piston
2nd gear piston hub
Servo cover oring
Hub oring
2nd gear piston teflon seal (outer and inner)
quart of fluid

Very simple to do as posted, maybe a 30 min job depending on if you have to remove the tranny cross member or not. Had to on the TBSS.

[Texsrt4]

i dont suppose someone has done a write up and part number list for the corvette servo swap. auto trannies are the one thing i havent dealt with when it comes to cars. everything else i have at least a decent working knowledge of, autos are new

[brantsz]

I decided to look at a few stock tranny tunes VS some that were done in the past with good results. I studied these changes and applied them to my tune and accomplished satisfactory results. My biggest issue was having to really push the throttle to drop from 4th to 3rd around a 45 to 50 mph. the TCC lock up to 90/100 was a good mod also. I will probably still look into the servo just for tranny life. My shifts are really firm with stock settings and 50% TM removed.

[brantsz]

Bringing this thread back from some time ago. I have installed a Billet Super servo for 1-2 and also for 4th apply. It actually shifts great maybe a little harsh but not to bad. The Low RPM Just above 1k the 1-2 is way too harsh, and I plan on lowing the shift pressures for this in this area after I run a scan.


Russ K would you mind looking at my tranny tune I have set up to see if there is any thing you would change. I am installing a Pro charger and would like to do what I can to help the stock tranny. I know it won’t last but I would like to do the best I can with it. I will attach my stock tune and the current on for easy reference.

[brantsz]

I lowered the 1-2 shift tables back to stock. Still really harsh at low RPM shifts would you guys recommend scaling back the FMC table? I know these servos are overkill but I got a great deal on them installed. I did copy and paste the lower MA/KPA column’s and shifted them over 3 rows and the 1-2 snap was still there. I put the FMC table back to stock due to it not changing much and would like to see what you guys recommend. I am not real secure in raising the MV to much for fear of loosing too much pressure.

[2therock]

@ brantsz, did you ever cure the hash 1-2?