Transmission + Transfer Case Troubleshooting

[Black-Syth]

Alright, with the current mods, the truck dynos 301rwhp. This is probably WAY below what the stock tranny can handle. The problem I have is that the transmission gives me an extremely hard and noisy shift at redline (open-throttle). I'm still under extended warranty, but everytime I bitch about it at the stealership, they never EVER solve the problem. What could I do to rid myself of these troubles. I'm tired of paying $200 each time for the deductible. I'm planning on spraying soon, and I don't want to blow this trans in the middle of a race or something.

Secondly, whenever it gets wet outside, the "Service 4WD" light turns on. All I have to do to turn it off is restart the car. Is this something serious, and is it do-it-yourself fixable?

[MTPockets]

I personally would not put a modded 300hp+ to a stock 4L60E trans. They are a good trans, but wont take that kinda pounding. Beef up kits are avail for them. As far as the service 4WD thing when wet, check the connections at the front axle disconnect and xfer case. I'd pull, clean and reseat all the connections I could get at.
G/luck
Joel

[jimmyjam]

how, pray tell, did you end up with 300hp at the wheels? thats huge!

[Black-Syth]

how, pray tell, did you end up with 300hp at the wheels? thats huge!

Honestly, I thought the results with all of the aftermarket stuff were a bit off. I'm going to dyno it somewhere else and see where it goes. I don't have THAT much aftermarket **** on my truck, so it might not be as high. For now, I'm going with those numbers because those are the ones I have.

[blandmiller]

Unless you have more than bolt-on mods, I would be very suspect of any RWHP numbers above ~225.

[HellHawk]

Are you using a G-tech or some other measuring device rather than an actual chassis dyno?

[Black-Syth]

Are you using a G-tech or some other measuring device rather than an actual chassis dyno?

Nope, it was a chassis dyno. I have a friend whose father owns a shop around here. Now, here's the thing, I'm questioning the integrity of these numbers myself. I did the math, and I should be jamming out between 200 and 220 horse stock. I ran a 211 rwhp my first run ever. Now I have an Airaid TBS, Cold Air Intake, Stage 1 Jet Chip, a custom exhaust, and other little garbage. I don't see how I could be tossing out 301 rwhp. I have a friend with a dyno down the street, we'll see what I dyno on his later this week.

[HellHawk]

Cool, do let us know.

Anyway, back to your problem. IIRC the 4L60E's are rated to handle 400 ft lbs of torque, BUT.. Only at 4600 rpm. So I think in haste the general threw the 4L60E's in our 4.2L TV's. I think it's the higher revving that kills the trannys.

[ScarabEpic22]

Cool, do let us know.

Anyway, back to your problem. IIRC the 4L60E's are rated to handle 400 ft lbs of torque, BUT.. Only at 4600 rpm. So I think in haste the general threw the 4L60E's in our 4.2L TV's. I think it's the higher revving that kills the trannys.
I think youre right, but man do I like to get on the gas and feel the engine rev to 6300RPMs before shifting. Runs sooo smooth until redline its crazy, absolutely no vibration at all and it seems to pull forever!:yes: :D

[Black-Syth]

Either way, I still need to figure out how to maintain it pretty well. I was thinking about a torque converter, but first I need to know how to fix the problem I've got.

[MTPockets]

I wouldn't sweat the trans thing too much. The 4L60E has been around for ~20yrs so parts and service are everywhere. As long as you dont do massive towing or neutral drop it, it should be fine. You can add an aux cooler or get a replacement pan like this with a drain plug to help with maintenance: http://cgi.ebay.com/ebaymotors/NEW-GM-4L60E-ALUMINUM-TRANSMISSION-PAN-4L60E-TRANS_W0QQcmdZViewItemQQcategoryZ33727QQitemZ80451 83434QQrdZ1

Joel