"Locker" Differential Question

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m75
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"Locker" Differential Question

Unread post by m75 » April 18th, 2018, 9:10 pm

Progress comes slowly....
The person I purchased my A2 from said that the front differential had been rebuilt and was now a "locker" diff.
My experience with the M151 series never included anything with a locking differential.

When replacing the front U-joints and suspension, I noticed a loud and distinct clacking sound about every 1/4 revolution of the side flanges. Would this be indicative of a locking diff?

If so, would it be possible to use a NOS rebuild lit to return it to original specs? The intended use of the truck is for on-road, not trailing which is what the previous owner did (the rocker panels are direct evidence of that activity.....).
Jim Peterson
SGM, 31B Retired 2015
1961 M151 -Sold
1974 M151A2, Working It!

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m3a1
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Re: "Locker" Differential Question

Unread post by m3a1 » April 18th, 2018, 9:18 pm

I'm admittedly spitballing with this answer but you don't discuss the presence of any kit that allowed you to unlock the thing so if there is none and if it was indeed locked up (by alternative methods, internally) you're gonna have to open that thing up and have a look-see. Old school method was to ( :shock: gulp :shock: ) weld up the spider gears so as to ensure the axles on both sides turned together.

Another question is, what did he do to the front differential?!!

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m75
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Re: "Locker" Differential Question

Unread post by m75 » April 18th, 2018, 9:23 pm

I believe that there will be no easy way out of this issue other than purchasing an NOS unit, maybe I'll land one of the mythical "quieter" units.

Regarding what was done to the front, it's still mounted on the truck, and other than seeping lube from every seal, I can't tell what was done to the interior portion. Purchase was three years ago, and I am no longer in touch with the previous owner.
Jim Peterson
SGM, 31B Retired 2015
1961 M151 -Sold
1974 M151A2, Working It!

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m3a1
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Re: "Locker" Differential Question

Unread post by m3a1 » April 18th, 2018, 11:15 pm

Well, you have no downside at the moment. Open em up and take pics cause, as you know, misery loves company.

Seals on the diffs are actually very easy, by the way. I think I documented seal replacement on my "restoration" thread.

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svramselaar
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Re: "Locker" Differential Question

Unread post by svramselaar » April 19th, 2018, 2:56 am

hi

i think you have a Ron rietfors modification
he used the intern from a suzuki SJ 410 or sammurai diff
it is normally lockt and unlock at a corner with a click

george

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rickf
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Re: "Locker" Differential Question

Unread post by rickf » April 19th, 2018, 9:55 am

If you don't want it then I will be glad to take it!

Sent you a text
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: "Locker" Differential Question

Unread post by rickf » April 19th, 2018, 10:06 am

With a lock-rite locker, or any automatic locking differential neither wheel can travel slower than the ring gear. So if you jack up the front end and have the transfer lever in two wheel drive then turn one wheel it will either turn the other in the same direction or it will give a ratcheting noise. The best way to check is to lock the transfer lever in gear with the wheels both off the ground, now try to turn the wheels and they will either turn in opposite directions for the standard open differential or they will not turn at all for a locker. NOW, Hold one tire with a little pressure like you are trying to roll it backwards and while doing this then turn the other tire in the forward direction. IF it is a automatic locker such as the lock-rite, then it will turn and make a ratcheting noise. If it does not turn then it s probably welded spider gears and if it make grinding or crunching noises and grabs and releases inconsistently then it was a welded unit that has become unwelded. :roll: :lol:
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: "Locker" Differential Question

Unread post by rickf » April 19th, 2018, 10:10 am

It would be very odd to put a locker in the front and not in the back, when turning in four wheel drive front lockers can be interesting to say the least. You have to be a hard core wheeler to understand and control driving a front locker. They are VERY hard on front axle joints. In two wheel drive they are transparent but noisy.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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