Break-in period for a new ARB locker?

[tdesanto]

I've always understood that there is a standard or relatively accepted break-in procedure for new ring and pinion drive gears. I don't think I've ever seen this concept disputed anywhere.

I was wondering about the pinion/ spider gears or any other component of an ARB locker for a rear differential. Is there any break-in period/ procedure I should follow for one of these?

I'm getting the RD155 for my truck next week. I'm already planning a trip the following week and I'm trying to decide if I should wait to have it installed to allow me time for a proper break-in period or if I'm being overly cautious and shouldn't worry about it.

I will be towing my AT Horizon on this trip and it will be for at least 1200-1500 miles. Almost 1/2 of that will be on the outbound trip. It will be broken up into 2 6-hour stretches.

I also plan to use Redline 75W/90 again, just like I'm using now. Some say it keeps things running cooler and that it creates a better environment for the gears with less heat and stress. That could just be marketing hype too, but I've heard it enough times to make me think there's some merit.

Any advice from folks with experience with these would be most appreciated.

 

[IdaSHO]

Typically a fresh rear-end requires 500 mile "no-towing" break in.

Im not sure what ARB specifies as a break in though.

 

[cruiseroutfit]

The '500 miles' on the ring & pinions has far more to do with the coatings that the ring & pinions come with from the manufactures and the fact that do to the slighly variying setup (ie backlask, pinion depth, etc) you are bound to remove some very slight amounts of material from the gears themselves, hence the fluid change. The ARB however has no 'adjustable tolerances', all are precisely set by design and checked at the factory in Melbourne (got to watch them do this . That said you are still re-setting the ring to pinon interface the the potential for some slight wear is there, more than anything its a good time to drain the fluid and verify it doesn't look out of the ordinary, etc. For that reason I still recommend it, though anywhere between 500-1500 miles would be fine (ARB recommends 1500 miles for the first fluid change and on used gears that would be perfectly fine imo)

I can't emphasize enough that an ARB Air Locker will be on of your favorite modifications if installed correctly. A hack install will quickly make it the vain of your life. Things like proper bulkhead location and air supply line routing both outside the diff and just as importantly inside the diff, especially with some of the newer two-peice carriers in whcih the seal housing is now on the opposite side of the carrier thus requiring the copper line to bridge the ring gear. They are very straighforward to install but again, make sure it is done correctly. Pressure test them before finalizing the install (bench test when possible) and check for supply line leaks before you drop that 3rd into the housing or button up the diff cover. There are a lot of axle specific caveats, several with the Land Cruisers that I am intimately familiar with and some with the Dana axles too ie oil drainage, etc. Make sure your familiar with these or ask your vendor as they should have the answer.

As for regular service for the ARB:
First 500-1500 miles & every 30k: fluid change. clean/replace breather
Every 7500 miles: check diff oil & inspect for leaks
After each use in water/mud: Check diff oil for contamination
After each use in brush/rocks: Check air supply lines
Every 6 months: Operate Air Locker to ensure it is in good working condition.

Keep an eye on your compressor too, things like the filter, moisture, etc.

 

[AlexJet]

Officialy its 1'000km with oil change of easy driving, no towing and no off-road. Practically I'd recommend double it to 2'000km and change oil twice. I always like to be on a safe side. My 2c.

 

[flyingwil]

The '500 miles' on the ring & pinions has far more to do with the coatings that the ring & pinions come with from the manufactures and the fact that do to the slighly variying setup (ie backlask, pinion depth, etc) you are bound to remove some very slight amounts of material from the gears themselves, hence the fluid change. The ARB however has no 'adjustable tolerances', all are precisely set by design and checked at the factory in Melbourne (got to watch them do this . That said you are still re-setting the ring to pinon interface the the potential for some slight wear is there, more than anything its a good time to drain the fluid and verify it doesn't look out of the ordinary, etc. For that reason I still recommend it, though anywhere between 500-1500 miles would be fine (ARB recommends 1500 miles for the first fluid change and on used gears that would be perfectly fine imo)

I can't emphasize enough that an ARB Air Locker will be on of your favorite modifications if installed correctly. A hack install will quickly make it the vain of your life. Things like proper bulkhead location and air supply line routing both outside the diff and just as importantly inside the diff, especially with some of the newer two-peice carriers in whcih the seal housing is now on the opposite side of the carrier thus requiring the copper line to bridge the ring gear. They are very straighforward to install but again, make sure it is done correctly. Pressure test them before finalizing the install (bench test when possible) and check for supply line leaks before you drop that 3rd into the housing or button up the diff cover. There are a lot of axle specific caveats, several with the Land Cruisers that I am intimately familiar with and some with the Dana axles too ie oil drainage, etc. Make sure your familiar with these or ask your vendor as they should have the answer.

As for regular service for the ARB:
First 500-1500 miles & every 30k: fluid change. clean/replace breather
Every 7500 miles: check diff oil & inspect for leaks
After each use in water/mud: Check diff oil for contamination
After each use in brush/rocks: Check air supply lines
Every 6 months: Operate Air Locker to ensure it is in good working condition.

Keep an eye on your compressor too, things like the filter, moisture, etc.

Well put Kurt.

 

[tdesanto]

Thank you, gentlemen, for the quick replies and the assistance.

Kurt, thank you for the valuable and well-articulated information.

 

[tdesanto]

Kurt,

How often does the pinion depth need to change when swapping in an ARB?I was told by the mechanic I've selected that the pinion doesn't have to come out. So, when ordering shims, seals, etc. today, I didn't order new pinion bearing races (as indicated is necessary for my diff) or the pinion shim kits for this reason.

 

[cruiseroutfit]

Kurt,

How often does the pinion depth need to change when swapping in an ARB?I was told by the mechanic I've selected that the pinion doesn't have to come out. So, when ordering shims, seals, etc. today, I didn't order new pinion bearing races (as indicated is necessary for my diff) or the pinion shim kits for this reason.

Never. The pinion depth is 100% relative to the carrier bearings and if they somehow change even with a new carrier and a different brand of bearings, you have far bigger problems on your hands

So for a locker install without gear change, at most you need is a new set of carrier bearings (and carrier bearing shims where applicable). Make sure to read up on the bearings specified by ARB if applicable for instance in the Land Cruiser realm there are a couple of different bearing options and different applications will need later model bearings, etc.

Standard caveat, the labor often isn't that much different for an ARB install (carrier swap only) and a complete differential rebuild with new pinion bearings. So if you might be worried about the condition of your pinion bearings ie high miles leaky pinion seal, etc), its the time to do it as often it only adds ~$75 at most in parts and maybe another $100 at most in labor (referencing Toyota standard pricing here, some vehicles may be wildly different.