|11-13-2011, 05:54 PM||eBay Motors #1 (permalink)|
Join Date: Apr 2009
transmission making a roaring noise in first gear
working on a 2001 gmc serria 6.6 2500hd allison auto trany ......ok so i got in my truck this morning and backed it up and put it in gear and roar roar roar even worse when i let off the gas truck has a lot of miles on it like 389,000 but all the gears work fine and dont slip sifts realy good just makes this noise .... only in first and gets louder when u let off the gas pedel ....... so this is what i have done i pulled the drive shaft put the truck in 1st and climed under it roar roar bad sound comming from the back of the trany sounds like a rear diff when the bearings are bad
2011 chevy 3500 lml
|11-13-2011, 06:17 PM||eBay Motors #2 (permalink)|
Join Date: Apr 2011
Location: Upstate, NY
Just a stab in the dark. 4WD? Maybe Transfer case? Check fluid in T-Case. I've heard funky sounds from bad T-cases. I'm ASSuming you already checked Tranny fluid and it's at proper level and good, not burnt.
John '06 2500 LT CC SB "LLZ" Duramax
PCV & Resonator "Fixed"
TransGo Jr. SC Filter Lock, LML Manifold, EGR Block, MA Rub fix on the bench, and chit for free time.
Dane: Mad Jack Racing
Tim: Power Labs Diesel
|01-11-2012, 02:40 PM||eBay Motors #4 (permalink)|
Join Date: May 2011
Im having this same issue. It just started yesterday, i searched and searched and haven't found anything yet. I hear the same roaring noise in D first through 2nd, then when it shift to 3rd it goes away. Happened to me on my way home from work. So i pulled the ING0 fuse forcing the tranny into "limp mode" and did just that limped home.
I have changed the Fluid and filter, fluid was a lil dark but wasn't burnt, then took the truck out on a test drive and same issue. Truck shifts fine no slipping or hard shifting, but by way of the noise i KNOW something isn't right. I have a OBDII scanner but the tranny isn't throwing any codes. the only code i have is a P0540 which is Intake Air heater circuit.
Many people are suggesting the transfer case but I have ruled that out because...
-1 when I pulled the fuse which removed power from the TCM and the truck remained in "limp mode" (3rd gear) I never heard the noise, so therefor im assuming its a transmission problem between 1st and 2nd.
-2 I rebuild my tcase 2 months ago, and have since put 6,000 miles on it since then
Im going to try and make a vid and post it, but any help would be greatly appreciated
truck is a 2004 LB7, CCSB, 4in exhaust