Transmission rebuild/cleaning

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Horst
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Re: Transmission rebuild/cleaning

Unread post by Horst » September 18th, 2016, 11:30 am

You are probably already aware that removing the gears we look at in the picture is super simple. Just don't loose any of the rollers when it separates in 2 halfs. The bugger is the countershaft below it.
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » September 18th, 2016, 11:44 am

Yea I was just having issues removing the transfer case half. I'm probably going to order new rollers if I am taking it down.
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Horst
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Re: Transmission rebuild/cleaning

Unread post by Horst » September 18th, 2016, 1:13 pm

In my limited experience, the transfer is actually worn before the transmission. If possible, get a new shaft for the intermediate gear and new rollers. There is a rebuild kit available containing all those parts. Ideally also change out the thrust washers if they look worn. I believe there is a minimum thickness given in the TM. Also, again if available, change the roller bearing for the brake drum. All of the above is very simple and straighforward and you will be greatly rewarded with a much less noiser transmission.

Check out my older post on this: viewtopic.php?f=3&t=9242

BTW, the TM says you need to press out the intermediate shaft. I have removed two of them and they always popped out easily with a light hammer and a drive. Also, don't forget to ensure that the rivets (or screws) holding the thrust washer are nicely covered with (black) silicone, otherwise it will leak there.
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 GTO,1982 E350 Skoolie, 1987 SJ413, 1987 911
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » May 24th, 2020, 3:42 pm

I’m going to resurrect this ap4 year old thread as I’m now opening up the transmission again.
After cleaning and resealing the transmission worked great for a while until the parking brake fell off and it ate the speedometer gear. “Let someone drive it around and they left the parking brake on”

So after that I think I overfilled the case with oil after draining it and ran it a little longer overfilled. Started to have second gear pop out while driving so I thought I would have to replace synchronizers. 110 buys a 1+2 gear of the eBays.....

Got the transfer case off with a little effort wasn’t able to pull off a spacer but the whole thing is in pretty good shape not much wear on the rollers or gear wear at all besides the speedometer gear. I have the rebuilt kit with new rollers and a new thrust bearing if I need it but I don’t think I’m going to use it.

Current issue is the rear upper output shaft
Trying to remove the bearing and I have the puller listed in the -34 manual and it doesn’t fit on the bearing at all were the snap ring was its to tiny.

Am I doing it incorrectly seemed like the first step was to remove the bearing and the rear shaft kinda slides out the back to get the gears out. I’m only going this far to inspect the lower gear sets on the counter shaft.

Gears and parts for the transmission seem rather expensive and hard to find can’t really find any bearings on the normal sights but should be able to find some kinda cross match for them off Napa


Sorry for my prolonged absence from here I got locked out and then bought an M35 that took a lot of my time for a while!
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » May 24th, 2020, 4:11 pm

Gave up on pulling it seemed like it was barely pressed in to begin with so some light taps with a punch on the inner race and it popped right out

I have to remove the front to get the main set of gears out it seems even though it says only remove if absolutely necessary
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » May 24th, 2020, 7:16 pm

So how much is to much to be missing off the countershaft gears?

Image
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

buzzinduzzin
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Re: Transmission rebuild/cleaning

Unread post by buzzinduzzin » May 24th, 2020, 7:33 pm

If there is rust on the gears you may have pits on the balls , races & rollers , is that a chipped tooth on the middle gear (first one forward of the straight cut gear ? ) & last; pull the plug : clutch shifter shaft to drain out heavy sludge that has probably settled in there. Caution ! there is a spring & ball that will come out & you will probably need to replace crush washer. Happy wrenching

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » May 25th, 2020, 7:15 am

Bought a new cluster gear and new synchro packs plus new bearings
Removed everything from the case to pressure was It dry and oil it the rod out any oil ports
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » June 11th, 2020, 5:40 pm

Rebuild completed over the weekend hope to have the power pack back in this weekend for a test drive

Anyone know what the prescribed break in produce is for a rebuilt transmission? All new gears and bearings only kept a few of the transfer case gears
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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rickf
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Re: Transmission rebuild/cleaning

Unread post by rickf » June 11th, 2020, 5:56 pm

Drive it normally. Did you use the regular dino oil and not synthetic? I have had problems with older transmissions using synthetics and the syncros not gripping as they should. They were designed for petroleum oil long before synthetics came out.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » July 4th, 2020, 1:21 pm

Finally got to drive around today very solid a little hard shift but I feel like it will wear in a little bit.

Did a full retune of my engine from the valves up it drives great now up to 30MPH at which point it stumbles and surges.......
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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raymond
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Re: Transmission rebuild/cleaning

Unread post by raymond » July 4th, 2020, 2:35 pm

2nd gear, 3rd if you count Low, is always a little hard to shift into, even with new gears, synchronizers, etc.
Raymond


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Husker
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Re: Transmission rebuild/cleaning

Unread post by Husker » July 4th, 2020, 6:19 pm

Yea 2nd was the hardest thought it wasn’t working!

Do you have a low! Or does the trans do more then just 4x4 when your push the selector forward?
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

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Re: Transmission rebuild/cleaning

Unread post by rickf » July 4th, 2020, 9:25 pm

1st gear is low, you would normally start out in second gear. There is no 4 wheel drive low.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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