ve7kilohertz

Hi Gang,

Well it's been a year or more now, since I had the oil pump tube/pickup failure in this case, which caused the fork pads to wear out and gouge the mode and range forks. Transfer case would pop out of 2x2 into neutral, usually while decel but once in a while under acceleration. Replaced those forks and pads and pump tube/pickup and all was good for the last year or so. 2 days ago, going up a new section of hwy at 100kph and bang, back into neutral, no real load on the engine, empty truck, no trailer. ***.

So I made it home no problem, pulled the PTO plate off the side and had a look inside. Very clean, oil level right up, shift fork pads mint and clean, everything looks good and tight. Mmmm. Okay, now what.

So here I am asking you wiser than I, what else could be causing this? It's a 2002 2500 6 speed with the NV241DHD. From what I have been able to research, the 241 HD doesn't fall victim to the dreaded broken snap ring on the output shaft, and I haven't pulled the tail shaft off yet. I am also wondering if the case may have stretched, or somehow, the input/output shaft spacing has changed, and the sliding range hub is not fully engaging the 2 shafts.

Anyway, I have 2 days to get this fixed as our last camping trip of the year is this Friday.

Your thoughts?

Cheers

Paul

Dane

Not sure I understand your post, but if I do...

Never run the truck in 4wd above 55mph
Never run the truck in 4wd on asphalt.

Doing either one of those is going to break parts in the xfer case.

gorms

Well if you only have 2 days you'd better pull it and split the cases to see what's going on. It's a pretty simple system, really the only things that will let it "pop" out of gear is the the output shaft sliding around, shifter forks worn/bent, or something is physically moving the linkage around, provided there isn't something really wrong with the mode hub inside.

With the tail off you should be able to rule out snap ring failure/something inside by seeing if the output shaft can move in and out at all.

Also before you drop it you can check the shifter arm with the linkage disconnected (driveshaft out also) to make sure you have positive shift points on that rooster comb inside.

ve7kilohertz

Hi guys,

Thanks for the replies....as you mentioned Gorms, I had to drop it and get it fixed so did that last night and found the snap ring in the tail shaft broken in two. Jeeez! I tend to research the heck out of a problem before diving into a project...trying to minimize the amount of work and time required, but in the end, I usually end up just ripping into it. Dane, I mentioned in the first post...2x2, not 4x4, and yes, never run em in 4x4 on dry pavement or above 55, agreed.

The output shaft could move over 3/8". I dug into the case all the way into the planetary and found the range hub sleeve damaged, the collar had worn a groove on to the sleeve and I had to pound it to get it off. Once off, I found another problem..the little teeth on the range sleeve that drive the planetary were worn at an angle, like they had been running partly engaged. See pics. One is the old sleeve, one the input gear, and the other is the new sleeve. Found a good used sleeve and range collar and replaced those, the input gear wasn't as bad and as I couldn't find one locally, just reused it. May have an issue down the road but will deal with it then. I reassembled it this AM and installed and took it for a run....good like almost new.

What do you think of the input gear wear? I hope it will keep me going for a while.

Thanks guys!

Paul

ve7kilohertz

And here is the complete service manual for the NV241DHD I extracted from the 2001 Dodge truck service manual.

I hope it will help someone else, like it helped me.

Cheers

Paul

Dane

Yeah, I saw that and wondered if I understood. Those gear teeth do look like they were run partially engaged. I dunno about that one, good luck.

ve7kilohertz

Ya, thanks! So far so good. Guess I should have said 4X2 instead of 2x2...was thinking motorbikes, or maybe I'm just gettin' old??

Cheers

Paul

Diesel Dave2

That's ok Paul........You had me going too..I thought...no..don't drive 100 kph in 4x4...

We are all getting old.....Good to hear your all fixed up now...

Dane

Yeah, but when you're ""over the hill" you go faster - right?

ve7kilohertz

Oh Crap! That means I should hit light speed sometime this year....when I turn 50. I keep telling my girlfriend I need to get out and find that red Corvette or a Harley...and a younger model girlfriend. I think she's a keeper though..she just laughs and eggs me on, afterall, she is the one that said I should be finding the Vette or Harley.

Cheers,



Paul