NORMAL NOISE???????????

[MIKE MOG]

AS MOST OF YOU KNOW I HAVE BEEN CHASING THIS NOISE IN MY TRUCK WHEN ITS LOADED. IM ALMOST THINKING THIS IS GOING TO BE A NORMAL THING. I HAVE BEEN TOLD BY A COUPLE OF PEOPLE THAT THE ALLISONS ARE NOISEY, CAN ANYONE VERIFY THIS? IF SO WHATS A NORMAL NOISE? I HAVE A 2003 4 DOOR WITH A 8 FOOT BED. NOISE IS THERE LOADED OR PULLING A CAMPER. SEEM TO CHANGE AS THE REAR OF THE TRUCK HITS DIPS IN THE ROAD AND JOUNCES OR GOES UP AND DOWN. HAD NEW SUPPORT BEARING, THREE U-JOINTS ON THE REAR DRIVE SHAFT AND THE REAR DRIVE SHAFT BALANCED. THE NOISE IS OCCURES BETWEEN THE SPPEDS OF 54 AND 64 MPH.
MIKE :mad:

[madmatt]

does this sound like your complaint?
Certain vehicles may exhibit a loud rattle, grinding or growling noise from the rear of the vehicle. The noise normally occurs at low speeds, typically 30 mph or less, and is noticed when hitting sharp bumps. This noise may be coming from the parking brake shoes. If a rear axle seal has been leaking axle fluid onto the parking brake shoes and the parking brake shoes are retained by the original style retainer, the shoes may begin to oscillate inside the parking brake drum creating this noise. If this is the case replace the affected axle seal/s, parking brake shoes, and install the updated parking brake retainer per bulletin 02-05-26-002a. Part Number
Description

88982875
Parking Brake Shoe Kit

88982879
Parking Brake Retainer Spring Clip Kit

[madmatt]

also see if it goes away when shifted in to 4wd. I don't recommend you run it like this often but is acceptable for diagnoising.

[MIKE MOG]

THIS NOISE DOES NOT OCCURE AT LOW SPEEDS. ONLY BETWEEN 54 AND 64 MPH, I DID SHIFT INTO 4WD AND HAD NO CHANGE. I TRYED TO DOWN SHIFT INTO 4TH BUT I COULD NOT TELL IF NOISE/VIBERATION CHANGED DUE TO THE HIGHER RPM. I DID SHIFT INTO NEUTRAL AND THE NOISE/VIB REMAINED THE SAME. SEEM TO GET A LITTLE LOUDER WHEN I STEP ON THE GAS TO CLIMB A HILL. LIKE I SAID I DONT KNOW IF THIS IS NORMAL. I BOUGHT THE TRUCK IN JULY OF 04 WITH ABOUT 33K ON IT. NOW HAS 36900 AND I CANT SEEM TO FIND ANYBODY THAT CAN HELP ME. I WAS ON LINE AND EMAILED SOME DEPARTMENT OF GM BY ACCEDENT AND THE LADY TOLD ME THAT ALLISON TRANSMISSIONS DO HAVE SOME NOISE. I DONT KNOW IF IM HEARING A NORMAL NOISE OR NOT. JUST DOSENT SEEM RIGHT
THANK YOU
MIKE

[MIKE MOG]

HEY MADMATT,
I FORGOT TO TELL YOU THAT I DID SERVICE THE REAR DIFF AND DID NOT HAVE ANY METAL IN IT. SAME WITH THE TRANSFER CASE. EVEN CHECKED THE MOTOR AND TRANS MOUNTS AND FOUND ALL GOOD. DID CHECK FOR BULLITIONS AT WORK AND CANT FIND ANYTHING THAT PERTAINS. CALLED TAC AND THEY CHECKED THEIR DATA BASE AND ALL THEY CAN COME UP WITH IS THE FRONT DIFF AND PINION BEARING. BUT I DID TRY 4WD. DONT YOU THINK IF IT WAS FRONT DIFF I WOULD HAVE A NOISE CHANGE WHEN SHIFTING ON THE FLY? I CAN FEEL THIS NOISE/VIB ALL THE WAY THROUGH THE TRUCK FROM STTERING WHEEL TO SEAT BOTTOM. DO YOU KNOW WHAT THEY MEAN BY A NORMAL TRANSMISSION NOISE?
THANK YOU
MIKE

[madmatt]

Normal? No, not really. The front Axle bulletin I was refering to pertained to a axle shaft clearence noise rather then the diff it self. Yeah though if it was the front axle problem i was refering to the noise should have stopped when in 4wd. Check you torque converter bolts to see if there tight. I seen this somewere in a buetin but can't seem to fnd it now.

[MIKE MOG]

THANK YOU MADMATT. I DID THINK ABOUT THAT. IS THER A EASY WAY TO CHECK THOSE BOLTS?
MIKE

[madmatt]

remove the starter. it's really not that bad to do.

[MIKE MOG]

thanks madmatt, i will wait until it gets warmer outside!
mike