Hi all. I'm still on the hunt for a 99-03 250 (or 350) 4x4 with a 6 spd, manual transfer, XLT or lariat in my area and my price range. I'm finding slim pickings so far and am starting to think maybe I could live with an auto.

The only forseable mods I plan on are the standard intake, exhaust, gauges and a mild chip. I don't tow at this time but that could change. Basically the truck will be a daily driver/occasional work truck replacement for my aged GMC 1500 (but with alot more style)

My question is what all can be done to these autos to ensure proper operation and better reliability aside from a rebuild by ATS, BTS, etc. ?

From the reading I've done I've come to understand they like to be kept cool and larger coolers may help but what about the sonnax kit or BTS valve body or simmilar items? Are these preventative measures that will save me from an unprovoked tranny puke, or are the problems with these trannies inherent in the design and to be counted on regardless. Am I correct in believing the converter is also a weak link?

This truck will never see a dragstrip. Maybe an occasional light to light but that about it. I'd only expect the same day to day driving reliability that I believe I will get from a 6 speed. Is this possible without an expensive aftermarket rebuild?

Thanks for looking
Chris-

 

I installed a factory tech valve body and Issopro temp guage. So far my trans temp stay in check without a bigger cooler. The valve body shifts alot faster and its suppose to raise shift pressures and torque convertor lockup pressure for better hold, longer life and cooler temps. The valve body ran me about 240 shipped from factorytechtransmissions.com