Topic: HELP !?! - Bearing in drivetrain going out???

[4RnrRick]

The bearing in question is always turning at the same speed (in relation to the motor/tranny gear) if the shifter is in neutral or low or high because its the secondary shaft. Your just sliding the hub coupler when you shift it and not actually changing the speed that particular bearing is spinning.

As for the oil clearance on the rear case, I think Marlin recommends in his dual case instructions that it should be .004" to .010" for the new crawler input shaft clearance. I would have to assume its suppose to be the same dimension for the rear shaft also but I don't know. Also I'm not sure what would happen if the clearance is too big as opposed to it being too small, the bearing would fry.


UPDATE: I just got everything back together, filled it will fluid 80/90W GL5 gear oil and did the same test as before and not rattle noise??? It appears I fixed it but I didn't change anything. The only thing I did was take it appart, clean it up, lube it and re-assembly it. So now I'm thinking that it "could be" the splines rattling from one conection to the other since I lubed those up with a high pressure grease during assembly or a bearing was dry and now it has lube..... I really don't know.

Will be interesting if Marlin can shed any light on this ?? ??

[brainlessfool]

  be happy

[4RnrRick [OP]]

Marlin are you out there? I tried calling you like you asked, but Chris said you where SUPER DUPER busy. I understand but I would still like to hear you comments.....

Thanks

[Marlin]

When i took last sat and sunday off, this put me 30 hours behind and on top of that, we had a customer come to pick up a truck that was abandoned 2 years ago and it was not ready needless to say, it really hit the fan.

Remember I told you about the green Benton high pressure grease? I recall having more problems when i used to sell the MC05 with the weaker then stock center bearing. I feel that adding grease to the output shaft did the trick.
We use white antiseize.

As i said before, i knew Rick would make it happen....

Marlin

[bloodsweatbeers]

I have a very similar problem.  Here are the specs.  85 4Runner, 22RE, W56-A, 2.28 front case, MC # 1095, mc 4.7 rear case.

I am hearing the same whirling, howling noise.  It happens at about 35 to 45 mph and gets worse at higher speeds.  It only happens when load is taken off of the drivetrain such as a downhill portion of the road when you take your foot off the accelerator.  If you push in the clutch when this is happening, the noise continues and you can keep it howling loudly almost to a dead stop if you hold the clutch in.  Putting it in neutral does not make the noise go away.

I wish I would have taken out the rear driveshaft and tested it again, but I don't think that the driveshaft is the problem.

Being not as gear savy as some of you guys (yet), I have been taking the "lets try this and see if it works approach" 
I replaced the clutch pilot bearing, throwout bearing, and went ahead and put a new MC clutch.  To me this seemed like the place that I would have been getting the most play in the drivetrain.  I put it back together and found that this was not the answer.

I now have the tranny/t-cases on the floor again and was planning on bolting my spare tranny up to the dual cases and putting it back in to see if it was a bearing or something in the tranny (A little background on the vehicle:  I purchased it, slightly use, not long ago.  when I changed all the fluids, I got a lot of metal shavings out of the tranny.) 

While I have the tranny/t-cases on the floor I am going to replace a cracked cover #1 on the rear case (frontmost section if you don't have it memorized) and also put twin sticks.

So, here is the question.  What do you guys think that I should do while I have it apart, given my above explaination?  After reading 4RnrRick's conclusions, I might just keep my existing tranny, lube everything?, and reassemble.  I don't really have the knowledge or tools to get to much into the internals of the crawl box or t-case, but I would appreciate it if someone could give me some specifics on what exactly should be checked and/or lubed while I have it apart.  Is it as simple as putting white antiseize on the splines of the output shafts?

Thanks in advance,

Coyote

[bloodsweatbeers]

So I have been reading some more, specifically:  http://board.marlincrawler.com/index.php?topic=41209.0

I need to take a closer look at my rear diff because I found a lot of metal shavings when I changed the fluid in it also. 

But more importantly, I just realized that the previous owner had the driveshaft with the slip end at the rear, so if I turn it around I may find that my problem is solved!?

[Jordan7118]

If the slip is at the diff, then that's stock. Not sure that'd make a difference for ya. 

[bloodsweatbeers]

I thought that I have seen them stock with the slip at the diff, but from what I read, turning it around might help?  It is easy to do, so I am going to try it.