I have a stock 4l80e with at Yank SC3000 converter. I have been getting a horrible rattle sort of noise around 1800rpm for a while now, but now I also have a pretty loud whine and i feel like the truck has alot less power. Also, the other day i put it in R when it was very cold out, gave it some gas, and nothing happened. I put it back in park and tried again and it was fine. I also noticed that when it's cold it seems like i have to give more gas to get the truck to go. when it warms up it seems better, but still not the way it should be. What do i do?

 

thats odd for that to happen to an 80e... are there clutch packs in the 80es? Sounds like there is a crack somewhere and your losing line pressure. Do you notice when you have your foot on the brake and shift from park to Drive or reverse does the truck pop into gear or is it normal? Also... is the whining noise only when your moving? at the top of the gears, beginning of the gears?

 

sometimes it does really slam into gear, not always. whining is only when i'm moving and gets louder the more gas i give i think. do you suppose something could have happened to it while it was being dynod last week? it was run in 2nd gear to 6000rpm. seemed like a bad idea to me, but, i'm not the expert

 

no... im shifting around 6500, thts fine. but ya, i think there must be a crack somewhere internally... no fluid anywhere right? You might not see anything dripping.. but look on the under side of the truck and see if there is any fluid sloshed on the underside... if there is, thats def not good lol. If you know of any trusty tranny shops.. bring it to them.

Dont bring it somewhere that'll tell you that you need complete overhauling and it'll cost around $2k... try and see if you know anyone that wont bust your *****, ya know.

 

Sounds like some of mine was doing. Mine was due to the TC being too long for my setup and it wiped the pump out.

Good Luck

 

just got back from new england transmission. they are trying to sell me a $3800 4l80e, but, also said my tranny is perfect. I guess the whining was actually coming from the whipple. at least now i know.

 

hmmm.. isnt 3800 a little steep for a used 4l80e? or is that new?

 

i think that 3800 tranny was a bulletproof one joe. every auto ive seen had clutches in it also.

 

May not be the problem, but I had similar incident with my '00 Z-71. I heard a strange whining noise, sounded like a bearing, the noise got louder with acceleration. I tried downshifting, to see what'll happen, and the noise got worse. Turns out my rear axle bearings were bad. It might be worth it to check it out.