# Transmission Shift Kits..good Or Bad



## jadartt (Mar 10, 2010)

I'm looking at installing a shift kit in my 4L60E to speed up the shifts in an effort to reduce heat production. Has anyone done this and did you like it or, would I be better to get an aftermarket performance tuner that also controls shifts and line pressure and stuff as well as a bit more power???

I've got a 2001 GMC Yukon XL so the closer the better as far as advice goes.


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## battalionchief3 (Jun 27, 2006)

Speaking for the 4L60E its generally a light weight trans. They put that trans behind full size trucks, cars, vans and even both of my S-10's have them. They are generally only good for 150k miles and then they burn up. As far as a shift kit I think its a good idea. People like a smooth shifting transmission, well that smooth feeling is actually the trans slipping into the next gear. Most people don't realize that. A shift kit or shift improver kit basically takes out the smooth shift by eliminating the weak springs and adding check balls or bigger pistons in the valve body to bang the fluid into the channels and applying the bands or clutches faster. This will give a firm shift. This also reduces heat. Slippage causes heat. This also puts extra stress on some of those items, kinda a double edged sword. Some of the factory parts are not as strong as they should be. I still would recommend it for towing. I also would recommend a huge cooler. Heat kills transmissions, period. If your trans ever dies and you get it overhauled, go to a good trans shop and have them beef it up. They can really hook you up. Stronger planetary gears, Kevlar bands and clutches and stronger converters. Plus you would already have a shift kit installed and a big cooler. Sorry about the rant.....go for it and good luck.

Here is a deeper trans pan

http://www.mag-hytec.com/

Here is the cooler I use

http://www.bmracing.com/PRODUCTS/Hi-Tek-Automatic-Transmission-Cooling-System


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## jadartt (Mar 10, 2010)

I plan on getting an additional cooler, but I want to get the temp gauge installed first to see the difference. Up here in AK, I need to ensure I get a cooler with a thermal bypass so I don't freeze the transmission out of service. Anyone every ran a cooler in -45F?

So it looks like a definate on the shift kit then.

Thanks


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## Lmbevard (Mar 18, 2006)

I'm not sure how much it will cost to have the shift kit and cooler put in, but I had my Dodge flimsy flyer beefed up with a cooler and all the bells and whistles for $3200. it had went out while towing the 5er back from camp. A 1 hour trip took us almost 3 hours because it kept over heating. never a bad idea to fix little problems before they become big.


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