1997 Jimmy Front Driveshaft Clanking/Wobble

[jvorrius]

Hi,
I have a 1997 GMC Jimmy 215k miles. It is maintained by me pretty well. I noticed recently with the windows open and driving at slow speeds down side streets I hear a metallic clanking under the vehicle. To make a long story short, I raised the vehicle on 4 jackstands today...with engine running....in 4 wheel drive....put it in gear and went underneath. Here is what I discovered. On the rear of the front driveshaft where it goes into the transfer case I could see a slight wobble and also pinpointed that location as to where the noise is coming from. Shut the vehicle off and was able to wobble the rear of the front driveshaft where it goes into the transfer case...and yes I did hear the same noise when I moved it by hand. Any suggestions as to what the fix would entail would be appreciated. I have rebuilt a few engines but don't want to get in over my head on this one. I do have the factory service manuals on this vehicle for guidance.

Thank you as always for help in advance,
James

[maxwedge]

Well. you need to determine if this is the shaft or bushing in the transfer case is causing this play, pull it out and look at what's what.

[jvorrius]

Thanks,
I will take a look at it today.

[jdmccright]

Could be a worn out U-joint. Unbolt the U-joint ends and then try to wiggle the end going into the transfer case. Hopefully, that will not have any play. Then check for play between the joint and the shaft. U-joint replacement is pretty straightforward, though I haven't had to do it yet on my Jimmy.

[jvorrius]

Hi,

I do want to mention that I decided last week to bring it to a local shop. I have known these guys for many years. They had to replace the vacuum operated switch in the front differental. Basically, the switch was causing the vehicle to run with a partially engaged front differential.

Thank you for all of your help and suggestions

James V.

[danorsemen]

I just had this problem a few months ago...She's getting up there in years and not aging gracefully. Hard to maintain being 10hrs away, only home 1 weekend a month.