• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Front-End Noise (Frt Differential?)

S

shafman1

GUEST
Hi, I just turned 3,000 miles on my AV. I have my transmission reprogrammed with the Hypertech III however, I don't think it changes anything at low speeds. What I notice is at very low speeds usually in the parking lot, I will get a pretty loud clunk in the front end when the truck shifts. It's not coming from the back and it only does it at very slow speeds.

Does this sound like a bad front differential? I don't have any noise at any other speed or while driving at high speeds. No vibration. Just the loud clunk and a pretty good jerk. ?????? ???
 
If you chose the "shift firmness" you may want to back it off, you may have discovered a potential problem - on the other hand, the firmness will snap up the tranny which is right behind the engine and that may be what you are experiencing.
 
I did chose the shift firmness which may be the problem, but why would it clunk. Also, the HPPIII only gives you two choices. A firmer shift or the original soft shift. ???
 
shafman1 said:
I did chose the shift firmness which may be the problem, but why would it clunk. ?Also, the HPPIII only gives you two choices. ?A firmer shift or the original soft shift. ? ???
Click to expand...

I know, on or off. When you increase the line pressure [firmness] your transmission is going to behave differently, shift faster, this may be what you are feeling.
 
gandolphxx said:
I know, on or off. When you increase the line pressure [firmness] your transmission is going to behave differently, shift faster, this may be what you are feeling.
Click to expand...

Do you think it will damage anything if I leave it? The firmness doesn't bother me, I just don't like hearing the clunk up front. :B:
 
shafman1 said:
Do you think it will damage anything if I leave it? ?The firmness doesn't bother me, I just don't like hearing the clunk up front. ? :B:
Click to expand...

Can't answer that, mine shifts hard, snaps me back, thats what the Transgo is supposed to do, not a "klunk" - PM Butch, he is a very good resource on these things.
 
Thanks for the info. I'll drive it again and listen more carefully.
 
Hummmmm...., I didn't get any Clunk on mine from the front end.., even at very low speeds.., it does shift firm at very low speed.., but never got any drive line clunking..., set it to stock, and see if it goes away.., if it does maybe it was causing it.., or..., its showing up a problem thats developing in the Drive Train.., Hope not.....
 
hey,

what is the hypertech III program for the tranny?? where can I get it and how can you change it.

Mine does the clunking thing as well, however the dealer and GM has a Bulitin on this, as normal. Do you think reprogramming the tranny will help.


Thanks

GKAvalanche
 
Check out the Hypertech thread under Performance Modifications. It tells you all about the Hypertech PPIII
\
Yes, it does make a big difference. You can order it online or from just about any of your favorite auto parts store.

The Hypertech part number for the 5.3 Liter is 30012 :B: ;D :0:
 
I just installed the HPP3 on mt K1500. No clunk, just very responsive, faster shifts. I like it !
 
:8: :C: :D: Iam screaming flaw hear a clunk have a crunching noise your differential is going just like mine did at 8500 miles, now the fun part three weeks in the shop I still don't have my truck. FLAW! FLAW!! FLAW!!! :8: :8: :D:
 
:8: to check if that crunching sound is your diff come to a rolling stop let off the brake don't touch the gas if you here a crunching sound your differential is going.
 
:B: :DI haven't noticed anymore noise from the front end. The only noise I hear now is from the locking differential which I've heard is normal. My last two Silverados made the same noise. I'm still keeping my ears tuned though just in case something does turn up. Thanks everyone for your input. I will keep it in mind if I hear the noise again. :D
 
:cautious: I've just hit 4400 miles and i noticed a front end sound, but it sounds different from what has been described. After driving for a little while, I get a noise like something needs to be lubed. It does this only when I make a right turn by turning the wheel rapidly (fast or slow speed). Any thoughts? And, yes the front end was lubed at last oil change.
 
Are you getting a sweaking or rubbing noise or just a noise when you first turn the wheel?
 
I hear a popping sound when the wheel is turned to the right. This happens when the brakes are applied at very low turning speed. The GM dealer in my area attempted to fix the problem by lubricating the part mentioned in the TSB.

Needless to say, the problem was not fixed. Any ideas
 
The noise I have is very similar to the sound of wet brakes when u slowly let off of them. Know what I mean? It only does it after driving for a bit, not as soon as I start it.
 
Well..this is an old thread, but I thought I would mention my Av had to take a trip to the dealer yesterday...same funny noises that everyone else described.

They called be back, saying the differential was 'about to blow' on me :-[

I'm driving an extended cab 03 Silverado until getting the Av back.

Wish me luck (y)
 
You must log in or register to reply here.
Back
Top