Hello,

Vehicle: 1985 F250, 460ci, 4WD, 8600GVWR, Dana 44HD TTB.

Intended usage: Mostly road, eventually with a camper shell and pulling a boat. BUT I also want to be able to go offoad, moderate terrain, usually sandy, nothing severe. Some snow possible when traveling with camper later on.

The engine is out now being rebuilt and should be done shortly. Next: The entire front is coming out shortly, new tie rods, springs, Shocks, bushings everywhere, etc... including the Dana 44HD rebuild.

I've been doing alot of research on these forums (for which I am very grateful) and on-line but there is not much info available using comparisons of differernt differentials.

Right now I'm down to either a Yukon Grizzly locker or the Ox Locker with cable actuated lock. I'm not interested in any air or electric operated differentials and the only reason I'm considering the Ox is it can be engaged with a cable

The grizzly locker is cheaper and I like that its operation is automatic in that it will unlock when going around corners. The down side is that I've read that this can be prone to issues when attempting to shift gears while going around corners and it reengages and also with driving issues on snow or other slippery conditions while going around corners in that it might "chug" going into and out of lock.

I like that the Ox is an Open differential until engaged and than it acts as a spool when engaged ( I think, I can't find out if it is automatic like the grizzly if going around a corner when engaged). I could find hardly anything on how it might drive and on other forums but most seem to like them

Can anyone here comment on their experiences with either differential and advise which might suit my intended usageand/or vehicle best? Any Pros/Cons of either locker?

Rgds

nonrev

 

I haven't heard much on the grizzly locker, I know yukon makes really good stuff. I don't hear of too many people running the Ox Lockers. I know one guy who was running them in his truck front and rear, and they worked awesome. However I later heard of him having problems with the cables freezing up from not being used. I am planning on building a Dana 60/70 combo for my 79 Bronco and I plan on using a Eaton E-locker in the front and a full spool in the rear. I have heard and read some pretty good reviews on the E-locker, a good friend of mine is running one in the front of his Bronco and he loves it. Hope this helps!
John

 

Tru-trac in the front. Fully automatic. Works like a limited slip til you put power to it and it tends to act more like a spool. No cables, no air, no electric.

I would never have a full locker in the front except for a dedicated trail rig. On the street, it limits how much you can use it.

Try steering a locked front on ice/packed snow....

 

Hi Stangrcr1,

One thing, and I could be wrong here and hopefully one of the drivetrain gurus will chip in. My understanding of the type of differential the Grizzly is an automatic type... the example used is that as the vehicle rounds a corner the outside wheel is turning faster and this causes it to break away from the differential drive and the torque goes to the inside wheel.

Wouldn't this be the same if one tire started to spin on ice? It would be spinning faster than the other tire and therefore break-away while the torque went to the tire with the most grip... just a theory but it seems the action on slippery ice would be similiar to the tire action going around a corner... ??

I'm going to check out the True-Trac... thanks

Rgds

 

Yes and no. The problem mostly comes if you are on the accelerator. Coasting around a corner, the locker SHOULD allow the cogs to slip and allow one tire to turn faster, but it has to overcome the spring pressure in the diff. If both fronts are truely locked, then the front won't steer on slippery surfaces.

That is why I like the Tru-trac as is allows the wheels to turn independently.

 

Hi Stang,

Have done research on the True-Trac and have just about decided to drop the other two options and go with the Treu-Trac. Fortunatly there seem to be alot of reviews on this unit on-line.

One question though. Several mentions that this unit can't take as much torque as some other units. Since I've got a 460ci, 3.54:1 ratio, 4WD with a 4L granny gear and I'll be putting a camper on top and pulling a boat this got my eye. Any comment?

Also it appears that there might still be some manufacturing issues. The most common failure mode seems to be when first installed within the first few days or 100 miles or so when they disintegrate catastrophically. Any info on this?

Also, have you experience with this unit?

Thanks,

Rgds

nonrev

 

Put a locker in the rear and leave the front open. You'll thank yourself later.

 

It should take the torque of your combo. Unless you are running over 35" tires. The bigger the tires, the more load on the diff/axle shafts/u-joints. Now we are talking about the front diff right?

The only ones I have heard about breaking were either serious offroading or improper installation/improper lube.

Even though I have not installed a diff for a street truck myself, I would have a reputable shop do the install so that if there is a problem, you can blame them. I have installed several diffs, r&p's for race cars that never saw the street, and never had one fail, but that is one area I will let a shop do it.

I just read the owners manual for the Tru-trac and they recommend max tire size of 32". Hmmm. Seems they may have dropped the larger axle sizes, possibly due to failures. I know they used to make them for the Dana 50 and Sterling.

Your part number would be 913A591 assuming you have 30 spline axleshafts.

The more I think about it, I would call Randy's Ring and Pinion and see what they say. They are my local shop for axles. 1-866-631-0196

 

After further thought, unless you are going deep woods or everglades, I would keep the front open and locker the rear, Detroit or Yukon, as Critter suggested.

 

Hi Stangrcr1,

Thanks for the info. The last I read on the True-trac was 35in tires also. I'm planning on putting 33in on the truck. Just over the 32in...

I found another link where folks are using the True-trac for racing rear ends and now complaints about torque issues on those threads... hummmm.

I thought that the reports of exploding true-tracs might be due to installation issues as alll of them were almost immediately or within a very short time/miles.

My largest concern about leaving the front end with open differential is that we get alot of rain and slick roads here in Fla and I assume that the LSD action of the True Trac would assist in breaking, especially when towing a load in the rain.

Any truth to that? I can live with the disadvantages if I can some extra for light off-roading and safety in slick road situations

Thanks again for all the info and help

rgds

 

in truth, neither 4x4 nor locking diffs have a huge benefit while braking. when braking, both front wheels recieve the same braking force and either hold or skid according to the combination of the force applied and the traction available. the locker really has no effect on that.
that said, a spool in the front will force one wheel to slip some during every corner, causing worse steering and braking than anything else. i realize you weren't looking at a spool, but i'm just giving perspective here.

that said, my DD has a powertrax in the rearend and doesn't have any problems until its on really slick stuff - and that 2wd

 

It is irrelevant what differential is in the front until it is locked in at the hubs. If you normally drive with the hubs locked in, then yes the diff will make some difference, but since that is not the normal case, it doesn't matter. Or is it?

Do you normally drive with the front hubs locked in and the xfer case in 2wd? I do that on my Superduty when bad weather is around so I can quickly shift to 4x if needed. But for normal spring through fall driving in the Northwest, the hubs are unlocked. And no I do not have auto hubs.

For the street, an open front will allow each tire to turn/brake/etc individually. Any limited slip could cause a sliding wheel to make the other slide by transferring all power there, possibly overpowering available traction. Off road, slippage is expected. Also, if locked in 4x on the street, at least one wheel has to slip or something breaks.

I would just put a locker in the rear and then see how it is for this coming winter season.

 

Hi Stan,

Appreciate the advise. I'm in Florida and reside there. Not much ice or snow sliding BUT we do get downpours and slick roads frequently enough in the summer.

I don't expect to be doing much driving with the hubs locked except maybe in the rainy season and occasionally to sling the lubricant around as others have suggested be done occasionally.

I was attracted to the True-Trac but will dive into an open differential a bit more. Is there any brand you or anyone else could suggest as being a good open differential?

Thanks

Rgds

 

To the OP... So why are you not interested in an air locker?
I have had one for years on my rear diff and has worked flawlessly.
Also the pump can be used to pump tires.

 

Hi,

I'm trying to keep things as simple as possible on this truck. Minimum of stuff to breakdown is the idea. I've had the engine rebuilt and had alot of the convenience electronics removed. Part of the reason for buying this truck was lack of power anything.

I have been to alot of threads on multiple forums here and elsewhere and one common failure mode of the air lockers was loss of air pressure. A common complaint frequently enough was people having to work on the air system in one way or another, mostly taking care of leaks or loss of air.

The differential I'm looking for is for the front drive, the Dana 44HD TTB. I'm still leaning toward the Truetrac but will investigate the advantages/disadvantages between the LSD (kinda LSD anyway) and an open differential today.

Rgds

nonrev