Hey guys, I’m really at a loss here I have no idea what’s going on with my 2000 extended cab 2500 auto trans. I was pulling my gooseneck probably 5k lbs, while accelerating my truck made a sound from under the floor, maybe trans or front end, sounded like a screech or squeak, and the whole truck kinda jumped. It kept doing it as I accelerated, now it’s doing that when I’m speeding up even without the trailer. Anyone have any idea what’s happening? Clutch?

Is it a 4X4?  

Yes it is 4x4

Any vibration when accelerating?  I'm thinking u joint front drive shaft.   Clutches and bands in the auto trans will just slip and not make noise.   

1 hour ago, IBMobile said:

I'm thinking u joint front drive shaft

 

If his truck has a CAD on the front axle (which I think it does), there shouldn't be any noise from the front driveshaft even with worn out u-joints because the driveshaft would not be rotating unless 4wd was selected.

 

@White wondee, I would first do a preliminary check of engine mounts, transmission mount and bell housing bolts, etc.  just to make sure nothing is moving around when it shouldn't be.  Check the rear driveshaft and carrier bearing, too.

 

- John

Actually it does still turn while unlocked. The shaft rotates slower but still it will turn. Does on my 1996 Dodge with CAD axle.

26 minutes ago, Mopar1973Man said:

Actually it does still turn while unlocked

 

This is true, but I don't think it is relevant in causing the "squeal and jump"  that he is experiencing.  That is why I stated it the way I did.   For example, if there was any resistance from a faulty u-joint in the front driveshaft, the driveshaft would simply stop rotating - the differential gears would allow for that.

 

- John

The best way I could describe it is, it sounds like the front left tire locks up for a split second. But I know that’s not happening, it feels like something is slipping. I figured it was something in my trans as it’s got pretty high mileage but I’m no expert here. It is most likely to happen while I’m accelerating while pulling a heavy load but happens occasionally daily driving 

Edited April 13, 20214 yr by White wondee

Could be the chain jumping gears in the transfercase, might binding up and causing the bang noise. 

Get some fluid from both the transmission and transfer case the one with glitter is the bad one.

On 4/10/2021 at 9:36 PM, White wondee said:

sounded like a screech or squeak, and the whole truck kinda jumped.

 

Did you feel like it slowed down (pitched you forward like a hard brake) at all or like something bound up and released?

 

Could be a wheel bearing that started spinning the race (happened to my dads 300c).. Front u-joint maybe, but usually they click and clunk, not squeal..

 

I agree with MoparMan on this one might be time to check internals of trans and tcase.

 

6 hours ago, Silverwolf2691 said:

 

Did you feel like it slowed down (pitched you forward like a hard brake) at all or like something bound up and released?

 

Could be a wheel bearing that started spinning the race (happened to my dads 300c).. Front u-joint maybe, but usually they click and clunk, not squeal..

 

I agree with MoparMan on this one might be time to check internals of trans and tcase.

 

It felt more like something bound up and released, reading all the information you guys have given me I think it’ll be my transfer case, i don’t think it’ll be my trans as I don’t drive hard at all and change the fluid and filter very often, the trans temp is also right where it should be. Thank you all for the great help.

Is the truck stuck in 4 wd? The drive line will bind up and jump on a hard service unless you are going in a straight line. 

On 4/12/2021 at 9:57 PM, Towrigdually said:

Could be the chain jumping gears in the transfercase, might binding up and causing the bang noise. 

You were right sir, drained the t case fluid and got some not so fun glitter haha. Thanks for the help guys I appreciate it

Torque king or quad4x4, whatever it’s called anymore, sells a good rebuild kit. Good timken bearings in the kit I got. 

When we rebuilt the t-case in my brothers jeep i believe we used a master kit from jbconversions.com. You have to look under np241c though.. There is a build guide in the article section on here i believe. The only hard part is there's 2 different input bearings across the years. And not a lot of info about what has what. One is a single row bearing, one is a dual row bearing. Its not hard to do the rebuild, should be a weekend if you have the rebuild and all the tools

 

Ive had to look for the same stuff because the rtv on my case failed and its starting to leak between the case halves, so if im taking the case apart with 210k on it, i might as well rebuild it. Especially since i ground the 4x4 synchro, or something, badly when i sled pulled last..

 

@White wondee what year and what tranny/tcase do you have? PTO port on the side of the tcase is an NP241DHD. I dont know what differences for rebuild parts it takes but i have found some. I think its in regards to the planetary, thats where a PTO would engage if you had one.

 

Torque King/Quad 4x4 is good stuff but their prices are high. 

Edited May 4, 20214 yr by Silverwolf2691

When I last pulled my transfer case off my 2002 Dodge I resealed it with Grey RTV silicone and not seen a leak at all.