2005 transfer case problem

[Devin05]

So we had our first snow storm here in ct and i got my plow hooked up and ready to go and when i put in in 4wd, I heard a clunking noise only under torque. As the day went on the noise got worse and i had a feeling that it was one of my u joints acting up ( being that dodge still isn't smart enough to put locking hubs on these beasts!!!) But i got under my truck after plowing and found that they were in in great shape so i have come to the conclusion that it is my transfer case. Now i don't mind buying a new one because it is a a fairly simple replacement but i don't want to buy the wrong replacement. I know it is a 273 d but i don't know if it is a 23 spline or 29 spline input shaft. The rest of the id tag is rotted away. I don't want to pull the transfer case just to check the spline because i need the truck to get to work the next day. Any idea on how i could figure out what number spline i have. Thanks!

 

[Blu-meanie]

I don't know for sure but I would think the vin number would be useful.

 

[Devin05]

I actually did plug in the vin on a decoding website and i was suprised on how many details it gave me about my truck but the only thing it said about the transfer case was that i had the on the fly electric case. I did however take a closer look at my rottin id tag and i read the last three digits on the second row and it read 650ad. After doing a lot of research i found that the tranfer case ending in those numbers have in fact the 23 spline input shaft. Has anyone ever heard of that? So im 85% sure i have a 23 spline case.

 

[seafish]

Well I hope that you are a 100% sure that the problem IS your transfer case, but to me, and from your description, it seems like a fairly LARGE jump to conclusions to say with any amount of cetainty that the TC is in fact the source of your noise.

In short, below is how I read your logic...please note that I am not trying to be mean or difficlut, only straightforward--

"I heard a clunk under torque, it is not the u-jpoints, so it IS the transfer case and I am going to replace it."




So, here are a few questions for you to help with further diagnosis. Please feel free to ignore them if you are confident that the TC is in fact the source of your clunk!!!

HOW did you determine that the ujoints were "just fine"??

(I ask this question because even under static load, the weight of these trucks tend to bind the ujoints when bad and it is nearly impossible to tell for sure unless you check them with the truck SAFELY!!!!!! jacked up, with the TC in neutral, and then check for binding and freeplay at each ujoint using a pry bar while turning them) The other, and also much easier way, is to use an IR thermomoter and check for a ujoint cap that is running hotter then the others after driving for a bit.


How many miles on the truck and what sort of use (ie...alot of snow plowing can easily wear front end parts on these trucks)??

Is it factory equipped with the snow plow package??

Are you familiar with the maintence history of this truck??

Did you inspect any other front end parts for wear that might lead to a clunk under torque (shock mounts and motor mounts immediately come to mind.)

Did you check the fluid level in the TC??


These are all important questions, and I am sure that there are more, but that's a start, at least, and I hope that it helps a little!!!

 

[petersonj]

Very well said, Seafish.

Devin05, in the absence of a IR thermometer, I have done a similar test for seized u-joints with good results. A seized u-joint will generate heat quickly, so for the test I wait a few hours to make sure the truck is completely cold. Then I drive the truck up to at least 30 mph, but for a short period of time to not allow the differentials and gearboxes to warm and transfer heat to the drivelines. I pull off to the side of the road and check each u-joint temperature by hand (carefully, in case one is hot). If all u-joints are running at a uniform temperature (probably cool or cold at your location) then you do not have a seized u-joint - but you still may have a sloppy one.

- John

 

[Devin05]

These are definitely good points. I checked all the u joints including the front drive shaft by putting the truck in neutral and sticking a bar in the joint and moved it back and forth and they were as tight as can be. Even the visual inspection showed that the bearings and the pressed joints were still tight and intact. I don't think it is the shock/ motor mounts because it only happens when in four wheel drive. The vin showed that it did come factory equipped with a plow package and as far as the previous owners maintenance/ upkeep: by saying he was a bit overkill on the maintenance schedule is an understatement. I have a huge folder of receipts and documents that showed that he loved his truck! I did try to check the fluid level but both the upper and lower drain plugs were stripped beyond belief and rusted shut on top of that. P.S the truck has 190000 miles on it.

 

[Motorhead]

You say you have the electric engaged transfer case. Have you checked the electric actuator?

 

[brods]

On the diesels the "plow package" consists of one level higher spring rate front springs and a flimsy tcase skid plate. The skid plate does a good job of collecting slush and snow which then freezes. When the driveline moves and shakes it hits the ice transmitting the impacts and vibrations to the frame and cab. At least it is easy to diagnose (just look to see if there is ice/snow packed around the tcase).

You mention the ujoints are tight, maybe too tight? On my 05 a ujoint was seized at the front driveshaft double cardian joint which caused a thumping, though I cannot remember if it made any noise. I have a freespin kit so just kept the hubs unlocked until it was fixed. There was no visual indication of anything being wrong. Turning the shaft by hand it was easy to diagnose. Before dropping $$$ on a tcase I'd try turning the shaft by hand with the tcase in 2wd and since you don't have locking hubs you'll have to have the front wheels off the ground (safely of course).

I did some shopping for tcase stuff a while back and came across this site: http://www.transfercases.com/ I know nothing about them and didn't buy anything from them so do your own homework before buying. The site does list pricing so you can do some comparison shopping. Maybe they can help you out with the spline count, though you can just pull the rear shaft and count the splines to be sure. Oops you said input shaft not output....ignore the part about pulling the rear shaft.

 

[CKelley1]

i will bet the transfer case is low on oil, pull the drain plug and see if a little oil and metal come out. the seal will go out and the oil does not drip on the ground to where you can see it. the parts to fix it is $260 and takes no special tools, i have never been in the electric one but there should be no difference

 

[cerberusiam]

Given the t-case plugs are stripped and rusted it is probably low on fluid and the chain stretched, time for a new one anyway or at least a rebuild. Auto trucks should have the 23 spline input, IIRC the 29 spline is for the manual trucks.

 

[Devin05]

Thanks guys! You definitely gave me a lot of solid info to point me in the right direction. Ill let you know what i come up with!

 

[RBertalotto]

In another thread I outlines the enormous amount of work I just had done on my 2006. When they pulled the transfer case to replace my transmission, we found a hole in the transfer case. Rotted right through! $1700 later for a very heavy duty Jasper transfer case and I'm good to go for another 200K miles.

 

[Devin05]

Ok so i replaced my transfer case this morning and it was actually pretty simple. It solved my clunking noise and the truck is 10x smoother during 4wd. Thanks for all the help!

 

[petersonj]

Thanks for posting the results.

- John