2nd Gen Non-Engine/Transmission Clunk/Clang in the drivetrain?

[DWeaver]

Hauling a load down the hill, the drivetrain would clang every time I let off the foot feed. When I stepped on it, no clang. Does it in all gears.



Quick check under the truck and could not pinpoint the noise. I am "guessing"that the trans output shaft is slipping a spline to the t- case when decelerating.



I was wondering if that has been a common problem with the NV 4500 and NP 241 hd?



I do understand how the search button works, and I will be removing parts until I find the source of said noise. Just askin, to see the scenery on the trip around the barn.

 

[NIsaacs]

Good job!:-laf I would check the u-joints first. Make sure there is no tension on the drive shaft first.



Nick

 

[mwilson]

I do understand how the search button works, and I will be removing parts until I find the source of said noise. Just askin, to see the scenery on the trip around the barn.

Very good!!!!



On the serious side I give a second vote for a hard look at the u-joints.





Mike.

 

[kcv67]

Same problem I was having could not find what the noise was until yesterday. The drive shaft was stopped just right and you could feel the play up and down in the u joint on the rear diff. Another way I found it was jack up one side and in gear rock the tire back and forth that is when I could hear the clanging.



Casey

 

[JMcCoy]

Probably the u-joints as stated above. It's not a bad idea to check the drive shaft carrier bearing (if so equiped) at the same time.

 

[DWeaver]

Well, I finally have the pick up in the air and all U-joints are looking good. No carrier bearing.



When I rotate the rear drive shaft no more slop than usual. The front drive shaft when rotated slops around.



I pulled the front diff cover and all looks good in it.



Could it be the t-case chain, stretched out and popping?



Next question is, what hard parts in the t-case usually need replacing? I do need to go through the t-case anyway, since from the orange RTV every where on it, someone has been into it.



I have just gotten used to having the work horse around and it is hard for me to give it up for a week while having the case out and waiting for parts.



Thank you for your thoughts on this.

 

[JMcCoy]

I don't think the chain will make noise in 2wd. I could be wrong though. Since there is orange rtv every where, that is probably the best place to start. Good luck.

 

[NIsaacs]

Well, I finally have the pick up in the air and all U-joints are looking good. No carrier bearing.



When I rotate the rear drive shaft no more slop than usual. The front drive shaft when rotated slops around.





By just rotating the rear drive shaft might not show a bad joint. Grab each one by the shaft and yoke and try to twist them. What about the front slop? What part shows this? I would drain the t-case and check for contamination. Sometimes a drive line noise can be hard to find, the noise seems to travel around.



Nick

 

[JR]

Ive had to physically disconnect my driveshaft to feel a bad u joint before. It was a sealed joint, and was froze up and extremely stiff to try and turn by hand. With the driveshaft connected, I couldnt feel any movement

 

[DWeaver]

Finally got to work on the thing. The drive shafts are out and all the joints are good. The diff's are good and now filled with new fluid.



The T-case is not so healthy. When I drained it I was screening the ATF. No chunks in the screen of the drain pan. I found them all stuck to the magnet, and in the pump screen when I split the T-case.



This is what was under the pump screen.

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SO, with the oil starvation in the t-case there are three planetary pinions that are shot, the front thrust washer in the planetary is gone, and the range fork is missing pads, and the range fork shifter collar is welded to the support sleeve.



I am not 100% certain that the t-case is the problem, when the parts get here and the case gets back into the pick up, I will let you know.