AMC 20 rear wheel bearings

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shimniok
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AMC 20 rear wheel bearings

Post by shimniok »

Wanted to double-check with others here.

1. The RR axle has sideplay of about 1/8" - 1/4" -- this is bad, right? I will take a look at the bearing/collar (no time right now)

2. Do the D44 and AMC20 use the same wheel bearing? E.g., National #A-10?

Thanks!
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'86 GW "Troubled Child" tc.wagoneer.org
360, TBI, 4" Skyjacker, 33" BFG MTs, WT D44+ARB, WT AMC20 + LockRight, CB 2m 6m 70cm, K0FSJ
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Lumpskie
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Re: AMC 20 rear wheel bearings

Post by Lumpskie »

I'm interested in learning about acceptable sideplay as well. Also, what years of wagoner use the AMC-20 vs the D44? (I'm 99% sure my '89 is a D44)

Anyway... Bump for you, Shimniok!
1989 Grand Wagoneer - Rebuilt 360, 2" Alcans, 10" travel Gabriel Guadian shocks.
1996 Land Cruiser - 1HD-T Diesel, Gturbo (23psi), Wholesale Automatics 442f, F/R ARBs, 35" Duratracs, ARB Rear Bumper, OME 2" lift, home built sliders and aluminum belly skid
2000 Honda Civic - Integra GSR engine, transmission, shift linkage and axles, 200hp, 33 combined mpg
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Re: AMC 20 rear wheel bearings

Post by shimniok »

All of my AMC 20 axle shafts appear to use tapered bearings/cones. Yet every parts store I see online lists a cylindrical bearing... ?!?! But when I look at the Crown wheel bearing kit at BJ's (et al) it shows a tapered bearing.

I remember running into this last time I looked for rear axle wheel bearings 10+ years ago.

What I have observed over the years:
1980-1985 AMC 20
1986-1987 AMC 20 (in a few) or Dana 44 (in most)
1988-1991 Dana 44

AMC 20 rear diff cover is perfectly round. If your rear diff cover is the same shape as your front diff cover, you've got a D44.
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Stuka
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Re: AMC 20 rear wheel bearings

Post by Stuka »

The M23 (FSJ AMC 20) needs tapered bearings. I ended up getting mine via BJ's way back when I rebuilt the axles. 1/4" of play is way too much, if you actually have that much, you need bearings badly.
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Lumpskie
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Re: AMC 20 rear wheel bearings

Post by Lumpskie »

Thanks for the information Shimniok and Stuka. (Now I'm sure I have a D44)

Hey Shimniok, did you have any signs that your bearings were going out before you took anything apart? I haven't looked at mine yet. I know they don't make any noise but the don't feel as smooth as my new front ones...
1989 Grand Wagoneer - Rebuilt 360, 2" Alcans, 10" travel Gabriel Guadian shocks.
1996 Land Cruiser - 1HD-T Diesel, Gturbo (23psi), Wholesale Automatics 442f, F/R ARBs, 35" Duratracs, ARB Rear Bumper, OME 2" lift, home built sliders and aluminum belly skid
2000 Honda Civic - Integra GSR engine, transmission, shift linkage and axles, 200hp, 33 combined mpg
2006 Mitsubishi Lancer Evolution 9 - 437hp/447ft-lb
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Re: AMC 20 rear wheel bearings

Post by shimniok »

The Jeep Parts catalog for the appropriate year lists J323 0115 as the OEM part for the bearing (c.f. 1981-1986 parts manual, Fig. 3-2900, on http://oljeep.com/).

Someone on this thread says that J323 0115 corresponds to A-10. Rockauto confirms that Timken SET10 (aka U399/U360L) is equivalent to J3230115. Same story on this site

Team Grand Wagoneer lists Crown #8130510 which has the 1-piece bearings. BJ's lists what looks like the same thing.

The only thing I've found in the TSM regarding endplay is that the "thrust block," which sits inside the spider gears, affects end-play if damaged. There's no mention of correct endplay measurement. There's no mention of adjusting endplay (as you would for the 2-piece Baby Jeep AMC 20).
Last edited by shimniok on Thu Aug 27, 2015 9:30 am, edited 1 time in total.
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Re: AMC 20 rear wheel bearings

Post by shimniok »

"TIMKEN SET 10 bearings are a two-piece unit that comes to you bonded together when you purchase it.
From the way your post reads, you have a unit-bearing in there, which is NAPA BR-10, which is incorrect.
The TIMKEN bearing, after it is installed will come out in two pieces when the axle shaft is removed." from this binderplanet thread

The BR-10's fail, apparently, leading to axles shooting out. The Timken's don't fail, apparently.
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Re: AMC 20 rear wheel bearings

Post by nograin »

About how much end play was there with the new bearings on? I assume you put new bearings on?

In a similar situation, nothing in the '82 or '85 FSM, nor the Haynes. My axles only have end play like a spark gap, .030 - .040" by eye. I'll measure at the next opportunity.
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Re: AMC 20 rear wheel bearings

Post by nograin »

Measured mine. 0.009 and 0.015". Not as bad as I thought. Timken wrote that anything over .021" should be replaced. So looks like mine are OK for now. Waiting to hear back on what to expect when they are new.
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