rear lockers

[tobyS]

I'm in the middle of a long term project building my 4x4 M35A3 and am planning axle modifications. First of course is removing one and mounting the suspension, I'm using M105 springs and frame mounts and not shortening the frame. With the 105 bed, I have a large area in front of the bed and behind the cab.

Since the rear axles are coming out, I would like to make modifications while they are out and I've been reading a lot about lockers...Detroit and air. I'm not wanting front pig locks but plan on hub locks there.

The air locks are a lot more money than the Detroit, but I like being able to release them at will. As this is a very high cost on top of the other modifications, I'm asking for your wise and sage advise. Should I spend the money and do it while the rear axles are out and putting on the larger wheel cylinders? Is this something that is easily done later...it looks hard to get the pig out once a bed is mounted and the axle in place. Note with springs, I could drop the rear shackle and rotate it down.

Am I missing something? Does having air locks on the rear and hub locks on the front sound like a worthwhile investment with soooo many other things to do right now?

 

[gimpyrobb]

Honestly, unless you have found yoourselfstuck in the rig as its built(its not built yet) don't waste your time. A locker fills a very small specific need that can be added at any time. I'd wait and see if its needed.

I have an old diff you can take and weld(turning it into a spool essentially) if you want to try it out.

 

[tobyS]

Thanks Chris. Mainly pushing snow or using the A frame crane on the front (I'm making it both front and rear) would be nice to selectively (not full time) go to the locked rear. But yea, good addition later. I'll make sure my rear axle can pivot down to give access without disconnecting brakes, etc. Planning now will make later easier. Plus I'll do more research and catch up on what is available that you guys have discussed.

It just popped into my head that I should have some shocks. Hope those 105 springs are not so stiff that shocks make no difference. My center structure will be adding a bit of weight, probably 3000# or so.

Do you have a transfer case PTO drive for a deuce?

 

[shannondeese]

I have a rear air locker in my Bobbed Deuce. I rarely use it and I wheel the crap out of my truck in the Florida mud. I have to say though that the few times I’ve used it, it was nice to know it was there. Unless you actually wheel your truck hard though I’d wait.

 

[rustystud]

I'll put in my here. Having had to remove the differential pumpkins in place before, it is a real pain in the butt ! Yes the cost of the air-lockers is high now, but in the future they will be more ! So having an easy access to the pumpkin now I would say go for it ! When your building your dream truck cost should not be a factor. OK cost is a factor, but this is something you can swing financially now or you wouldn't have mentioned it. Years from now when your wheeling your truck and you get stuck bad, you don't want to be that guy who says "MAN I wished I had just spent that extra money and installed those air-lockers ! " . I have also learned over the years that if it doesn't get done now, then the chances of it getting done later are very slim to none !

 

[winfred]

my truck has a detroit in the front and its ok offroad but once i installed mrap wheels/tires it became impossible to steer on pavement, locking hubs was the answer to steering but now i have to lock em if conditions require front drive, i plan to move the center section to the rear axle and go air lockers in the middle and front when i have a spare 2k and the time, and nothing better to spend them on

 

[tobyS]

Yea, the cost is a factor, unfortunately. I still have (5) tires to buy, but I have 4 descent 14.5's, so that expense can be put off. Don't have the 105 bed yet either and have a lot of frame work for the center winch, too... +seats, a new door, tranny with PTO... It's not like I NEED another project.

But this is an item that is burred far enough that doing it with the axle out seems way easier (if I do it at all).

Rusty is right, when you don't do it up front, the chances of doing it later are maybe only 10% doing it later.

Thanks for your thoughts...axles are coming out soon and at a minimum, I'll make sure that lifting the rear frame will make the axle pivot down for access. If I come across a windfall (sell commercial property), it will go to the top of the list.

 

[cattlerepairman]

The open diffs have a very specific vulnerability. See the picture, courtesy of Torquewrench.


When you get all three wheels (or two wheels, in your case) on one side spinning, it's game over. This is where lockers make the difference.

I think that it really depends on your budget. If you do ONE thing, I would suggest to put an air locker in your rear (while the axle is out, I think that is a smart plan) and plumb the air to the front as well, seeing you are running air line anyway, ready for a hook up at a later time. I agree with you on the control aspect of air lockers. There is also an electric variant that has good reviews. I would not want a Detroit style locker in the front, ever. I know...paranoia...it will not click in when the front drive shaft is not powered, so it is technically safe for on-road use. I just...don't like the thought. I want a switch!

I have not pulled the trigger on lockers but the lack of them severely influences where I am willing to take my Deuce.

 

[tobyS]

In a lot of ways it's like my little 4x4 tractor. I can have one front and one rear spinning and I'm done until I push the foot lever and lock in the rear axle. I may only use it 2-3% of the time, but pushing hard or backing out of a hole...it works and I would be SOL if I didn't have it. I'm not sure but I think my PU has something like a locking differential because coming into my drive, turning on gravel, I can hear and feel the inner rear tire slip in the gravel. Traction in snow is excellent. I want to use the deuce locally on road, but I have 43 acres of sand. Please post any links you may have to companies selling them.

 

[Floridianson]

I would not want a Detroit style locker in the front, ever. I know...paranoia...it will not click in when the front drive shaft is not powered, so it is technically safe for on-road use. I just...don't like the thought. I want a switch!

Do believe with lockout hubs in the front then Detroit locker is fine. Without lock out hubs in the front then the Detroit with or with out the transfer case front drive in gaged it will still ratchet wearing it out. Detroit is always locked and only unlocks when enough force to over come the spring is put to one tire or another or one tire spinning faster than the other as in a turn.

 

[tobyS]

I'm not going with differential locks in the front, certainly not Detroit full time, but I plan on putting on hub locks. Air (possibly electric) differential lock is only going on the one rear axle (4x4). Being an A3, I have air for the TC front drive, so air lock seems logical over electric.

I'm not up yet on how the different manufacturers function to lock, but air pressure going through rotating bearings or gears sounds potentially problematic. Is reliability or leaking air inside the housing an issue? This might be where some poor quality models would fail.

Any links to good engineering would be appreciated, most of the ones I found in older threads now show "error message".

 

[rustystud]

I'm not going with differential locks in the front, certainly not Detroit full time, but I plan on putting on hub locks. Air (possibly electric) differential lock is only going on the one rear axle (4x4). Being an A3, I have air for the TC front drive, so air lock seems logical over electric.

I'm not up yet on how the different manufacturers function to lock, but air pressure going through rotating bearings or gears sounds potentially problematic. Is reliability or leaking air inside the housing an issue? This might be where some poor quality models would fail.

Any links to good engineering would be appreciated, most of the ones I found in older threads now show "error message".

Air-lockers have an extremely high success rate. It is rare to have one leak. If you look at the design schematics of an air-locker you will see that air pressure is only needed initially to "move" the locking ring. Once it has moved you don't need air anymore, until your ready to move it back. The "seal" in an air-locker is not a "rubber" seal either. It is a "metal sealing ring" like in a automatic transmission. It will last your lifetime. Really.

 

[gimpyrobb]

Im not sure if they are still out there or not but at one time there was a kit to put a lock-out hub on a stock rear axle. I know it wouldn't work well with Toby's 4x4 truck, but ive been thinking of doing it to my 6x6 with a locker in the middle axle.

 

[Floridianson]

ARB would be my choice above Detroit.

 

[tobyS]

Im not sure if they are still out there or not but at one time there was a kit to put a lock-out hub on a stock rear axle. I know it wouldn't work well with Toby's 4x4 truck, but ive been thinking of doing it to my 6x6 with a locker in the middle axle.

Sure Chris, I would too if it was staying 6x6. Only one would relieve the stress in a turn of the back following a slightly smaller circle than the front rear axle. I think it requires a splined axle shaft, must be part of the kit. I thought about going a different route, making a cover plate using a stamped tank end and flange and just remove one axle. Then I went 4x4 and that changed.

 

[tobyS]

ARB would be my choice above Detroit.

I think so too, but on the rear, with only one axle, the Detroit probably wouldn't be too bad.
The frame is not shortened and the axle is 14" behind the center of the trunnion, so not bobbed and with longer wheel base. For about 700 difference, I might consider it though.

 

[rustystud]

ARB would be my choice above Detroit.

Mine too. The Detroit Lockers are great but extremely hard on equipment. Especially axles and side gears.