View Full Version : 4L80E Trouble HELP!

Big Blazer
02-05-2007, 06:24 PM
Yesterday I was driving my suburban(91 3/4ton 2wd) just towing 2 quads and the trailer maybe 2000 lbs total and I lost reverse and overdrive and you have to rev it to about 4000 rpm to get it to go into 3rd fluid level is good not burnt or anything maybe a little on the thin side but thats about it. I dont understand the truck only has 140000kms on it and it was an old mans before me and I baby the thing, the only thing i was doing different then i ushually do is down shifting to slow down, that couldnt cause any problems i doubt, or could it??? I was told it could be possibly the bands or the clutches. I dont know a whole lot on auto tranny's so any help would be great

02-06-2007, 11:39 AM
Sounds like you blown clutch band, drop the pan and check for shrapnel.

In The Zone
02-06-2007, 12:12 PM
i have heard nothing good about these transmissions...

specially when used for towing or any thing other than just propeling the vehicle

typical pressure problems accumulators and such not lasting and allowing premature wear of clutch bands ect.......

if u continue to tow with this truck look for other transmission options before repairing it..

Not really a chevy guy but a tranny is a tranny..

i could be talking out my ass though...

02-06-2007, 04:12 PM
Sounds like you blown clutch band, drop the pan and check for shrapnel.

i agree ..... gear pins are aluminum ...need to upgrade to steel

and they are kick ass trannys can be built up to handle 600+ hp and 1000 ft/lb torque

02-06-2007, 04:14 PM
o ya check out tciauto.com for their upgrades then buy at local cuz their shit is for way tooooo much HP vehicles

02-06-2007, 11:10 PM
i agree with checking the bands.
also check sensors for leakage that could cause false readings.

if you downshift alot repeatedly it can sometimes flatten the fins on the torque converter causing excessive slippage.

02-18-2007, 01:03 AM
time to pull a lame 454 and swap in something with 12 valves or swap in a th400 with no od, good mileage is fer hondas right?