Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum banner

Help !!! A4wd "banging" In And Out

4K views 9 replies 6 participants last post by  justinj 
#1 ·
Hello, I recently purchased a used 2003 Envoy SVT with the 5.3L Vortec V8, and am experiencing some difficulties with my A4WD system. whenever the system is engaged the front differential quite noticably "bangs" in and out ( in all weather conditions). I have read on other forums on this site about this topic, and yet I am still unable to place even a shard of an idea of what may be causing this issue. any help regarding this issue would be greatly appreciated.

P.S the front differential functions properly in both the 4HI and 4LO positions.

Much thanks, Sean
 
#2 ·
:tiphat Welcome :tiphat Did you mean a 2003 Envoy SLT? Have you checked the fluid levels in the front diff. and transfer case? Many on this forum have had a problem with a studder/shudder in A4wd. Changing the transfer case fluid clears it up. My only other thought would be a loose connection causing the transfer case to shift in and out of 4wd.:m2:
 
#3 ·
Thank you very much. I will certainly look into your suggestion :). any idea on where the fill or fluid stick is for the front dif? .. and yes i did mean the SLT:bonk:

P.S , Earlier in the day, i was following a friend who was driving my Envoy ( I was driving his 93 Blazer) and as we entered a wooded section of the highway, i noticed the rear lights flicking on and off. I am curious if this may be a sensors reaction to the difference in brightness and compensating, or if there may be anelectrical issue, or possibly a computer malfunction.

Much Thanks, Sean
 
#6 ·
First thing is to check the fluid level in the T-Case. If you're low or the fluid looks contaminated or other than light BLUE, change the fluid pronto! Use either Autotrac II or Royal Purple SynchroMax fluid, they're the ONLY two fluids formulated to work correctly in our transfer cases. (The SynchroMax may be easier to obtain, its sold at many auto parts stores, the Autotrac is a dealer only item).
 
#9 ·
As YLAB said "First thing is to check the fluid level in the T-Case. If you're low or the fluid looks contaminated or other than light BLUE, change the fluid pronto! Use either Autotrac II or Royal Purple SynchroMax fluid, they're the ONLY two fluids formulated to work correctly in our transfer cases. (The SynchroMax may be easier to obtain, its sold at many auto parts stores, the Autotrac is a dealer only item). " I don't think that will stop the hard engagement of the 4x4 in 4AUTO. The only thing that will stop that is to let up on the gas when it starts spinning.:m2: However With an '02 if the transfer case fluid hasn't been changed it is probably due. I bought 2qts of Auto-Track II fluid from the dealer @ $8.00/qt and a pump from Harbor-Freight for$6.00. It took about 1 hour to change, but that included rotating all 5 tires.
 
#10 ·
Hello, I recently purchased a used 2003 Envoy SVT with the 5.3L Vortec V8, and am experiencing some difficulties with my A4WD system. whenever the system is engaged the front differential quite noticably "bangs" in and out ( in all weather conditions). I have read on other forums on this site about this topic, and yet I am still unable to place even a shard of an idea of what may be causing this issue. any help regarding this issue would be greatly appreciated.

P.S the front differential functions properly in both the 4HI and 4LO positions.

Much thanks, Sean
did you ever fix this issue
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top