Shift kit in 175K mile tranny?

[Benm109]

As some of you might know from my last thread, I helped my friend install a shift kit in his 97 Z28. Since I've done this, it's made me want to put one in my transmission.

My concern, and reason for posting this, is that the transmission (it's a 700R4, 4L60 if you want to be technical) has over 175K miles on it. I am currently having absolutely no problems with it, but I am starting to want that feel of a shift kit in it. The ATF doesn't look great, but it doesn't seem to be burned or really dark in color at all. There seems to be a lot of debate as to whether shift kits prolong or shorten the life of a transmission, and I'm personally torn between this argument. I've been doing a lot of research on the internet, but it just makes me more undecided. So, what's you guys opinions on shift kits in high mileage trannies? I'm open to any opinions or advice.

[Kevin - Blown 95 TA]

The general consensus would probably be that you need the tranny freshened, then add a shift kit at the same time. The shift kit would probably make a new tranny last longer, but on a high mile one, it might just mask existing wear and slipping clutches. If I had an engine/trans with 175k on the clock, I would sit pat, or freshen it up. I wouldn't hotrod it as is.

[Benm109]

That's pretty much what I'm thinking of doing now. I think I'm just going to keep the tranny stock until it gives out, and then I'll just rebuild it and add the shift kit (and a couple of other goodies, too ) then. And, honestly, there's still a lot more I need to do to my car before I really need a shift kit anyway.

Thanks for the help.

[LS1 TA]

I put a shift kit in my 1989 RS camaro when it had about 150K on it. It was great for about a month. Those 700R4's can be expensive when the decide to go. Anyway I gave up after that costly lesson and bought a formula 350 firebird for almost what it would have cost for a new tranny.

[Joe 1320]

The general consensus would probably be that you need the tranny freshened, then add a shift kit at the same time. The shift kit would probably make a new tranny last longer, but on a high mile one, it might just mask existing wear and slipping clutches. If I had an engine/trans with 175k on the clock, I would sit pat, or freshen it up. I wouldn't hotrod it as is.

Exactly what you should do.

[wanamaro]

arn't you suposed to run a tranny cooler with a shift kit in. i heard stories of trannies blowing from heat and people that don't put in a cooler?