Bearing install t90 shaft

4x4M38 · Post by **4x4M38** » Thu Dec 08, 2016 9:15 am

Hey RickG, Oilly,
Is it the season up there for installing bearings on the T90
shaft?

I figure you guys just leave the bearing on the kitchen counter and the shaft on the porch over night, then slide them together before breakfast....

RICKG · Post by **RICKG** » Thu Dec 08, 2016 1:40 pm

rgmutchler · Post by **rgmutchler** » Fri Dec 09, 2016 3:51 pm

Brian,
I take it you got your T90 case and are putting it back together.

4x4M38 · Post by **4x4M38** » Fri Dec 09, 2016 8:41 pm

Hi Ralph!
I have a good case from Ken in Cali. Now trying to balance Christmas with buying the necessary replacement parts so I can do just that.

All the stuff that wears out has.

just the parts will be more than half what I paid for the jeep up front.

I'm sure that sounds familiar to many......

Derstrom · Post by **Derstrom** » Sat Dec 10, 2016 3:35 pm

I literally just did that.... Put the shaft on the front porch and heated up the bearing. Got the "stinkeye" from momma for putting a bearing in her microwave but it went on pretty easy.

4x4M38 · Post by **4x4M38** » Sat Dec 10, 2016 9:36 pm

Microwave!

Post by **wesk** » Sat Dec 10, 2016 11:16 pm

Must have been a plastic bearing.

southpw · Post by **southpw** » Sun Dec 11, 2016 6:39 am

You guys are going about it all wrong.
The proper way is to grind the inner diameter of the bearing with a die grinder until a minimum of .072" clearance to the shaft.

4x4M38 · Post by **4x4M38** » Sun Dec 11, 2016 8:06 am

Ah. Well, actually had not even thought of that.

I learn something new every day!

Post by **wesk** » Sun Dec 11, 2016 1:36 pm

Before grinding do verify the type fit specified for the bearing in that application.

There are three general categories of fits:

1 - Clearance fits for when it may be desirable for the shaft to rotate or slide freely within the hole.
2 - Transition fits for when it is desirable that the shaft to be held precisely, yet not so tightly that it cannot be disassembled, this is usually referred to as a Location or Transition fit.
3 - Interference fits, for when it is desirable for the shaft to be securely held within the hole and it is acceptable that some force be necessary for assembly.
Within each category of fit there are several classes ranging from high precision and narrow tolerance (allowance) to lower precision and wider tolerance. The choice of fit is dictated first by the use and secondly by the manufacturability of the parts. Fits may be specified according to the standards of Geometric dimensioning and tolerancing.

Most of the preferred dimensions are listed in the appropriate Powertrain, Body & frame Manual under Repair and Rebuild standards in either TM 9-1804B or TM 9-8015-2.

Derstrom · Post by **Derstrom** » Sun Dec 11, 2016 6:41 pm

Wrap the Bearing in a wet paper towel. Microwave on high until the steam flashes inside, about 1 minute. As long as the towel stays wet, it won't arc and it won't get hotter than 200 deg f. It's efficient and effective.