bad driveline clunk...not slipyoke

[lb7lbz]

alright the truck is an 05 reg cab diesel 4x4. recently while driving I heard a loud clunk from somewhere in the driveline. bad enough so I turned around and babied it home, which it happened several more times on the way. I thought it sounded like it was coming from the front diff so I drained the fluid, checked out ok. still not convinced I pulled the front driveshaft and both cv axles and went for a ride. clunk is still there. so I guess that eliminates the frontend. next I drained both the transfer case and rear diff as well as pulled the cover off the rear diff. fluids and rear diff inspection were ok. just pulled the rear driveshaft and drove in 4x4 and the noise was still there so now it looks like transfer or trans. I put truck back in 2wd (with no rear driveshaft) and put it in gear and spun just the trans. no noises at all. seems truck needs to be under load. any ideas??? without ripping into the trans or transfer I am stumped. please help I need this truck back on the road asap

[rapidoxidationman]

Have you lifted the truck off the ground and tried to wobble the wheels? Worn front hub? Any lateral movement pushing or pulling on the rear axle? Loose brake component? Loose spring mount? Worn bushing on the suspension?

[lb7lbz]

I have had the whole truck in the air on jackstands and ran it up to 60mph and cant get it to make the noise. On the ground I can sometimes get it to make it by stopping quickly from slow speeds even with the rear driveshaft removed. Frontend is all good , bearings,balljoints,cv axles, front diff etc.

[lb7lbz]

So today i pulled the starter to check the torque converter bolts and they were all tight. One more thing eliminated i guess. At this point i guess the transfer comes out next for inspection then if that checks out the trans is nxt. Not looking foward to this

[DmaxMaverick]

You drove it with the CV shafts removed?

If so, you'll need new front wheel hubs. They are NOT designed to bear the full weight of the truck without the shafts installed and torqued.

Unless you eliminated the hubs (before you drove with the shafts removed), they would be my first guess for your clunk and noise. They may be now, in any case.

[lb7lbz]

Yes i did. About a half mile total and the hubs were already eliminated before i did so

[lb7lbz]

Put the truck on jackstands again and got it to make the noise. Even in 2wd so there was nothing turning in the frontend. Its a random clunk and its definitely coming from the t-case. Time for her to come out. Will post my findings when i know

[MajMike]

Maybe rear driveshaft needs new u-joints? Mine did and it clinked and vibrated something awful.

[DieselDavy]

I know it might sound crazy, but I'm with Major Mike. I once had a noise that I had narrowed down to the tcase. I removed the tcase (not disconnecting the rear ujoint) and had a transmission shop go through it. They declared it quite healthy for it's miles and told me to look elsewhere. Upon re instllation of the tcase, I moved the shaft just right and noticed something. The rear ujoint was SHOT! Somehow the driveshaft transmitted the sound that ujoint was making. Myself and another observer were sure the noice was coming from the tcase......
Check those ujoints again!
Dave

[rapidoxidationman]

What does the transfer case fluid look like? Maybe pull the bottom plug and drain it all, see if it has metal flakes or dust in it. I'd imagine that if something inside failed enough to begin making noise it will leave evidence in the fluid.

[lb7lbz]

Mike and dieseldavy maybe u didnt remember but in one of my above posts i said i drove the truck with the rear driveshaft removed and the noise was still there. As far as the fluid in the t case i drained it from the normal plug and not the one on the very bottom of the case. The fluid looked good with no metal. Maybe i should have drained it from the bottom but now its pointless cause it has to come out anyway. Off to the mechanics shop cause i dont feel like pulling it in my dirt driveway

[DieselDavy]

Hi Towman,
You are correct, I did foget you drove it without rear drive shaft.
I hope you find something soon. I sure can drive you crazy eh?
Dave

[lb7lbz]

no you don't drive me crazy but this problem has. came out of no where, parked the truck fine one day and 5 miles into the next day it starts this. logged over 500k miles towing on my other 2 dmaxs and I havnt seen this one before, which is a rarity after that many miles logged. dropped it at the shop today so sometime next week I will have the case to open up for myself to inspect. will post results

[lb7lbz]

so my guy finally got the case to me today, only a month later but whatever. the smaller shift fork is smoked and the range hub it slides may be as well. what causes this? the other shift fork is in perfect condition and to my knowledge the case has never been run dry. any ideas?