np242 Planetary Gear Assembly Q

I am in the process of rebuilding my transfercase. The reason for the rebuild is I drove for about 60K with about 4 inches of lift and no SYE. Minimal vibes but recently they started getting worse.

Upon further inspection, I realized that I could wiggle the slip yoke/output shaft and figured that was causing my increased vibes. Purchased a new chain and 242e-maskit and started tearing into it.

Now, I am putting everything back together. While inspecting the planetary gear assembly (aka differential?) I realized that there is a little bit of play in it.

Here is a pic of the part with arrows pointing to the part that has play in it.


If this is a problem, where can I get this part? Please don't say stealership item only.... :eeks1: LOL

TIA for any info.

Jeep on!

i've not dealt with these guys, but they seem to have their act on. appear to have parts.

http://www.rsgear.com/NP242Jeep.htm

also, i would call tom woods' company. they make a SYE and CV shaft for the 242 and can tell you what fails due to the vibes. i called them earlier today because my fat boy has a bad case of the jeebies, so i will be installing their kit next week.

http://www.4xshaft.com/

Post what they tell you.

How much is a liitle bit of play? is it rotational play or side to side or front to back?
How many Total miles on this transfer case?

Did you do a good visual inspection on all of the components when you tore it down, did you notice any wear on any components, any spots that look to have been heated? Any cracked, worn, broken or unseated snap rings?
Did you turn all of the bearings (esp the input & output bearings) by hand to check for rough spots?

There is going to be some play in any gear assembly, I would have a good look at the gears and planetary housing for any sign of wear if there apears to be little or none, I would keep assembling & get it done.

I just finished rebuilding the 242 in my wife's XJ with 200k miles on it (never done before) I was actually quite suprised to find almost no wear. It had a cracked case due to an accident & I had to swap cases with one that had the wrong input shaft.

crawldaddy said:

i've not dealt with these guys, but they seem to have their act on. appear to have parts.

http://www.rsgear.com/NP242Jeep.htm

Post what they tell you.

Click to expand...

Thanks for the link but, I just called this place and the sales person was RUDE! She quoted me something like $350 for the assembly.. Ummm....NO! I found another for $118 at... Cyberjeep

As far as calling TW, I will save that for a last resort. I feel bad calling him and asking for help because I have decided to probably go with the RE H&T SYE over his.....

sys_eng said:

How much is a liitle bit of play? is it rotational play or side to side or front to back?
How many Total miles on this transfer case?

Click to expand...

There is a fair amount of play side to side, enough to make me wonder. If I push back and forth in the direction the arrows are pointing it even sort of clunks. As far as I know this is the original case and my XJ has just under 200K

sys_eng said:

Did you do a good visual inspection on all of the components when you tore it down, did you notice any wear on any components, any spots that look to have been heated? Any cracked, worn, broken or unseated snap rings?
Did you turn all of the bearings (esp the input & output bearings) by hand to check for rough spots?

Click to expand...

I was surprised to see how good everything in the case looked when I took it apart. I was stumped as to what was causing the play in my mainshaft. All the snap rings were in place and nothing looks too worn down. I will re-check all the bearings tonight but initially none of them really looked bad.

sys_eng said:

There is going to be some play in any gear assembly, I would have a good look at the gears and planetary housing for any sign of wear if there apears to be little or none, I would keep assembling & get it done.

Click to expand...

I am going to take the assembly apart and post a few pics of the internals for some opinions tonight after work.

Thank You everybody for your help.

I ordered the TW SYE & CV DS today. Chose it over the RE because the RE has the C-clip doing most of the work holding the shaft in the case.

Thanks for the heads-up on rude behavior. I'm taking RSgear off my list.

Ok, I took another look at those bearings and they don't feel as great as I firs thought. Mainly, I could feel some play in the bearing when I tried to mimic the motion shaking the driveshaft up and down would cause.

Also, the piece in the first picture with the arrows pointing to it moves up and down about an 1/8 of an inch.

I took some more pics...

Here is the inside of the ploanetary gear assembly. Picture taken from opposite side as the original. The arrow is pointing to where I can create about a 1/8 inch gap.


This is the side of the mainshaft that goes into the planetary gear assembly. There is some visable wear but I didn't think it was too significant, what do you think?


This is the other side of the mainshaft where the sprocket that drives the chan attaches. The side that connects to the slipyoke. Again, visible wear.

Anybody? The transfercase is still spread out on my workbench in the garage.

Do those gears look too worn down?

I am thinking I might just give it a shot, if not... take the darn thing apart again.

Any help would be appreciated.

Can you feel any wear on the gears at all, or is it just polished? if it seems to be just polished I'd put it back together. It's real tough to tell by pictures how worn things are. If the bearings were worn they may have been causing the vibes and caused some of the wear on the main shaft.

sys_eng said:

Can you feel any wear on the gears at all, or is it just polished? if

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I don't think you can feel the wear on the gears at all. I just called TW... I think I am going to just go with his SYE and see what he has to say about the planetary gear assembly.

Since my case is already torn apart, I will just ship out my tailcone and mainshaft to be modified and not have to pay the $400 core. I wouldn't be saving much going the RE H&T route and buying a driveshaft somewhere else so I might as well go with the best right?

I will update when I get this figured out.

Thanks again for all the input.

T-cases have a surprising amount of sloppiness in them almost everywhere except the bearings themselves and the surfaces of the shafts they ride on. The sloppiness makes machining and assembling easier and helps make up for any misalignment in the entire assembly. If your chain isn't stretched and your bearings are tight I would just put it back together and run it.

If you're really concerned I can check one of my spare t-cases as I currently have one apart in my garage.

Bender said:

T-cases have a surprising amount of sloppiness in them almost everywhere except the bearings themselves and the surfaces of the shafts they ride on. The sloppiness makes machining and assembling easier and helps make up for any misalignment in the entire assembly. If your chain isn't stretched and your bearings are tight I would just put it back together and run it.

If you're really concerned I can check one of my spare t-cases as I currently have one apart in my garage.

Click to expand...

Bender, Thanks for the reply. The old chain didn't look too bad but I got a new one since I was tearing it apart anyway. I never had any grinding noises just some play in my rear output. I also just replaced all the bearings and seals with new ones. I am thinking I am just going to put it back together.... after I send in my mainshaft and tailcone to TW to get redone for the SYE. :yelclap:

If you could check the planetary gear assembly spare you have for the amount of play that would be great. Basically, grab the part the arrows are pointing at and lift it. Mine comes up about an eighth of an inch I would say.


Off topic... Bender, does that have anything to do with Futurama?

Bender checked his part and let me know that there is some axial play in his also. I just got the mainshaft back from Tom Woods along with the other pieces I need to put it all back together and measure for the driveshaft.

I also ordered and am in the process of insalling T&T Boomerang Shackles before I measure. Those upper shackle bolts are a bear.....

:repair:

Tom Woods really does have customer service. He got the part back to me super fast and was very friendly and helpful on the phone. Thumbs UP for TW.

I hope to get it back together this weekend.

It's a little late but...

I got it all put back together and it's working great. The rebuild was a success and I have actually driven about 6K since the rebuild. I guess if it was going to blow up it would have already...

So anyway, I don't think the play in the planetary gear assembly was a problem because everything seems pretty tight now. No more play in the rear output shaft.

Just installed some shims in the rear and it rides REALLY smooth compared to before. I guess I didn't realize how much it really was vibrating. I always thought it was "minimal vibes".

Thanks again :: and everyone who replied.