m1028 locker

[johnsr]

i have a 1985 m1028. it has dual rear wheels and a np208 transfercase. this would make it an a3? but my real question is, i just put a new gasket on the rear diff and found out it was an open diff, am i supost to have a locker in it?

 

[scrambled]

I bought the dana 70 rear axle out of a dually 1028 a few years ago and it had a full case detroit locker in it. Someone might have gotten tired of chirping tires and swapped in an open diff.

 

[rnd-motorsports]

If it doesn't have a detriot locker in the rear somebody swapped it out a 1028 should have a posi in the front also!

 

[johnsr]

well i did whant to take a look at the front diff. where can i pick up a good locker for the rear? cheap realy cheap?

 

[scrambled]

Really cheap? Weld the spider gears.

Maybe a used posi from ebay and some new clutches.

 

[rnd-motorsports]

If the front is still posi and has not been bothered there will be a tag on the front cover held on bye one of the cover bolts. If I remeber correctly it says use limited slip fluid only its normally on the top right bolt as you look at the axle from the front.

 

[battlebuggy]

The 1 ton CUCV trucks do not have a Detroit Locker in them from GM, someone would have Bubba-ed one in there if it has one in it.. And they are not oper diffs either from GM for mil sales. They had a GM Gov-Loc combination posi/locking differential which is a fully locking unit triggered by its wheel slip detector. Until the wheel slip reaches the present speed the locker remains open unlike a Detroit Locker. When it is unlocked it has a clutch pack that acts as a limited slip. After the clutches wear out that feature goes away and it acts as an open unit when you test it up on a jack or lift.

 

[johnsr]

so do you have a pic of what the Gov-loc looks like? and are thy a good off road unit. i hate driving on pavement.

 

[rnd-motorsports]

battlebuggy the 5/4 ton m trucks all had the detriot locker in the rear from gm and the 1028,1031 maybe others had a posi front dana 60 axle a clutch type. the m1008 had an open or non posi front dana 60 the only m truck that had the gov-lok you stated was the m1009 (blaser) in the rear with 3:08 gears all the pickups had 4:56 gears check out this page http://www.classicmustangs.com/military_trucks.htm has a litle info to let you know about these trucks there are many others

 

[12vctd]

SO battlebuggy, can you please explain to me what makes a gm gov lock work. YOu seem to be implying that the gov lock doesnt have clutches that wear out either. Every one I have rebuilt had clutches as well. And I have removed many un bubba installed detroits from the M1008 and M1028 trucks. Now you would be correct to say a M1009 the blazer has a gov lock! Also you need to look up some info on the Detroit Locker made by true trac, as when they operating as they should and the driver coasts around a corner and does not keep power they unlock as well

 

[sarge1]

I bought the dana 70 rear axle out of a dually 1028 a few years ago and it had a full case detroit locker in it. Someone might have gotten tired of chirping tires and swapped in an open diff.

I was wondering about this. My M1008's rear tires chirp as I make most slow turns(seems like the wheel weight is coming off of). Is this a typical thing for when the locker is working? I kind of thought maybe my locker was shot because of this symptom.

 

[eric_banks32]

With a "good" locker your tires will chirp at times when making a turn. All of the 5/4 CUCV's had a detroit locker. Only the 10 bolts in the m1009's had the gov loc. The m1028 had a posi unit in the front diff. The m1008's had an open dana 60 front diff and the 09's had a open 10 bolt front diff. READ THE FAQ'S AT THE TOP OF THE PAGE.

 

[sarge1]

With a "good" locker your tires will chirp at times when making a turn. All of the 5/4 CUCV's had a detroit locker. Only the 10 bolts in the m1009's had the gov loc. The m1028 had a posi unit in the front diff. The m1008's had an open dana 60 front diff and the 09's had a open 10 bolt front diff. READ THE FAQ'S AT THE TOP OF THE PAGE.

Sorry, wasn't trying to threadjack or anything. I know what diff's my truck has but hadn't owned a true locker before so I didn't know. I'd searched a lot of things but hadn't looked into this one before.

 

[DrJekl]

I am not sure what type of locker is in the CJ10 but I have two of them with lockers and two without. Both Dana 70 and I think a 35 spline axle. Supposed to be a Gov Lock as I understand it but both seem to be normally locked as opposed to the GovLock normally open configuration. If you want something like this for your rear, let me know how many spline axles your 70 is running and I'll figure out what type locker is in these and verify the spline count. These have 4.88s on them so the 4.56s should bolt right on.

For the posting regarding the lockers, the Dana 60 locking front differential, as stated above, is a clutch type called the Trac Lock. Great set up but the one in my 1031 I use at the farm, I hate it on wet grass or slick surfaces. The wheels turn but the truck doesn't!

 

[scrambled]

The dana 70 did not come with a gov lock. Those were made by eaton for GM axles. The 70s should be detroits.

 

[DrJekl]

Really. Every write up I have seen on the CJ10 lists the locker as a GOV LOCK. I am pulling the engine from one of the CJ10s this weekend so that will give me an excuse to pull the differential cover. It is not a Detroit or a limited slip as it is normally open and locks up on wheel spin. If all the write ups are correct, what do I get? How about $1? I only know what I have read.

 

[ODdave]

GOV-LOC is GM ONLY! (aka GOV-BOMB) - Uses a fly-weight governer to lock a ramped gear that applys presure between the clutch pack and side gear. fly-weight locks into another weight (heavyer "flipper") that prevents HIGH SPEED engagement


TRAC-LOC & PWR-LOCK are DANA ONLY -
trac-loc- looks like a conventinal 2-pinion open diff but with clutch plates on each side gear, works souly on preload
pwr-loc- has an enclosed case with 4 pinion gears, uses ramped cross pins to apply more presure to the side gear clutch plates as more power is delivered. -personal favorite-


DETRIOIT LOCKER - is a product that is instaled in a normaly "open" carrier on 14bolt gm axles, has its own carrier on others, to provide a TRUE LOCKED axle configuration wether it be from the factory or owner
TO MUCH OF A P.I.T.A. TO EXPLAIN, look it up

 

[DrJekl]

Jeep used everone elses crap. The CJ10 has a Nissan engine, Dodge transmission, GM steering column, Ford style ignition and so on. I understand the type of differentials. Got it, I appreciate the tid bit of knowledge there.

Is it possible that the CJ10 program required a special run of carriers with a Gov Lock style locker? The axle is 82" wide with 3/4 width spring perches to work on the CJ5 length Wagoneer frame.

I'll get in there this weekend and see what it is. If it is somethig you may want for your axle, let me know and I'll verify the spline count on the axle shafts. Found some other info about ownders having a Power Lock differential in their D70s in the CJ10a.

 

[ODdave]

Jeep used everone elses crap. The CJ10 has a Nissan engine, Dodge transmission, GM steering column, Ford style ignition and so on. I understand the type of differentials. Got it, I appreciate the tid bit of knowledge there.

Is it possible that the CJ10 program required a special run of carriers with a Gov Lock style locker? The axle is 82" wide with 3/4 width spring perches to work on the CJ5 length Wagoneer frame.

I'll get in there this weekend and see what it is. If it is somethig you may want for your axle, let me know and I'll verify the spline count on the axle shafts. Found some other info about ownders having a Power Lock differential in their D70s in the CJ10a.

I think it should have dana axles, i have never seen GM axles under a stock jeep (cant say they did not do it though) , get a picture of the diff cover and the carrier and post them!

 

[DrJekl]

The rear axle is a Dana 70 under the CJ10 as previously stated.