Mechanical Shift Kit or electronic shift kit???

[GMC Hauler]

I have seen the electronic "shift kits" that shunt power away from the line pressure control solenoid in the 4l80E transmission, but is there any kits that you install in the valve body of the transmission, and is there any advantage to these kits? I am familiar with installing shift kits as i have installed several. I see that Jet makes one. Has anyone used this one? can we get a pro/con list to each one. Thanks..

[Turbine Doc]

I went with the mechanical kit B&M recommended this themselves over their electrical kit, mine came with 2 set ups race or tow, I had the tow installed, one thing with the mechanical kit the body had to be drilled out, so to go back to stock means a new body.

Mine is causing intermittent hard shifts with the Heath reflash, which also has a modded shift curve to it pretty agressive when both are combined, still on the fence for decision to de-tune reflash shifting or get a stock body and pull B&M kit.

[GMC Hauler]

Thanks for the reply. I didnt think about that (doubling up the kits for too harsh a shift), as I will be ordering the computer kit from Heath soon. Does the mechanical kit do anything different or "more" than the electronic kit does? I wouldnt mind poping the cover and dropping the valve body if the mechanical kit had more features that i wanted.

[TurboDiverArt]

I too have the B&M kit. I have had no trouble. The drilling that is needed is in the separator plate, not valve body. Needing to go back to stock is just changing the springs back and getting a new separator plate. You won't want to go back. Shifts firmer but definitely not harsh at all. You can also feel the TCC lock up much firmer. I used the Tow setting as well. Just remember the drain plug install.

Art.

[Mainous]

I ran an Autotrans Interceptor for about 4 months and found it to be too harsh on the 1-2 shift ao I switched to a mechanical shift kit from Transgo.
The Intercepor had adjustments for line pressure and Torque Convertor Lockup. Even after dialing the line pressure to it's lowest setting I felt the 1-2 shift was still too harsh although that was my only complaint. The Transgo kit did require valve body drilling and its a bit more of an advanced project for the do-it-yourselfer, but I love the way it shifts now. You can select different settings with it as well by drilling different size holes in the separator plate. Got mine off of Ebay along with a new separator plate and deep cast pan. It's a good idea to switch over to synthetic fluid at the same time.

The Interceptor is for sale if anyone is interested.

[damork]

Check with Sonnax, they make several fixes for the 4L80E. They are at www.sonnax.com. (http://www.sonnax.com.) Also the Shift Kit by Transgo is popular, their basic kit addresses some of the few weak areas of the 4L80E. They now have a website www.transgo.com. (http://www.transgo.com.)

[Diesel Dan]

I installed the transgo 4L80E-HD2 kit in my '00. Do recommend it. One thing it addresses is a pressure relief valve so if the ECM or force motor acts up a pressure spike won't damage the trans. This was/is an issue with the 4L80E.

[GMC Hauler]

I checked out both the B&M and the Transco kits, and the sonnax site says access is forbidden. The thing i am curious is the Trnasco kit. What is the "hold/backshift to any RPM" option? Is this an option to hold the transmission in that gear and only that gear? Is there any differences between the two kits?
Thanks for the replies so far. I thought i had read somewhere that the mechanical shift kits fixed some potential internal problems with this transmission, as i am all about correcting the factory problems. You guys just confirmed it for me.
When i put the kit in, i will switch the pan over to one with a drain plug and more capacity, as i hate taking transmissions apart without a drain plug. Does anyone have any recommendations to a pan, and what type of synthetic you would run?

[TurboDiverArt]

Regarding the transmission. My suggestion is to install an additional cooler regardless if you tow or not. I just put a large B&M racing stacked plate between the radiator and the fan. Dropped temps dramatically. Even without towing, on a 90-degree day after being on the highway with TCC locked up, temps would rise when off the highway to 230 sometimes before the additional cooler. It would take about 10 minutes to cool back down to below 190. On the highway the temps would never be above 170 or so when it was hot outside. Towing I saw temps sometimes rise to 260 before either of the coolers (hottest point). This is in stop and go traffic, not on the highway.

After the additional cooler I have not had temps above 180. I think it blipped to 185 right off the highway but within a minute the temp was down to 170, and that's with the A/C on. For $100 it's money well spent. If you're going to do it, get the biggest one. The B&M 11

[Mainous]

GMC Hauler,

I purchased my Transgo kit off of EBay from Oregon Performance Transmission using a "Buy it Now". They have a Hughes Performance Deep Cast Pan that I would recommend. Like I said, I bought a new separator plate as well. I was glad I did because there was wear where the check balls ride on the plate. I used Mobil 1 synthetic fluid because of easy availability.

[Mainous]

GMC Hauler,

Forgot to answer the question about the hold/backshift option. You won't use that option. It's for a manual valve body racing set up.

[damork]

Here's a link to one of the Sonnax locations that specialize in 4L80E parts:

http://www.transmissionspecialty.com/parts/main.htm

With regards to a pan, I believe you can gain more in cooling with a 29000 btu cooler. I added a TruCool unit in place of my stock unit, bought the 2 wheel drive oem pan which has a drain plug and added a port for a temp sensor. Temp has never been over 175F in the pan and the whole works was about $125, pan and cooler included (less the fluid).