ARB locker issues in Cold weather

SO... I have a 2005 with the 8.4 and RD89 ARB locker in the rear. The locker has been rebuilt and worked well until the cold weather hit. Below 30F the locker locks but the compressor runs every 5-10 seconds. After driving around it slows to about every 30 secs. ARB denies any cold weather issues with seals or anything else. Other sites have mentioned the RD89 having issues and ARB gave them some advice including using PB blaster to prevent the seals from freezing.

Has anyone else had this issue??

 

I'm going through this right now..

Here's the email I just shot to ARB:

ARB -

I’m having some issues with an ARB RD89 that’s installed in my Tacoma 8.4” rear differential. The locker was purchased used, and installed in January 2013. It had been working flawlessly up until about October of 2014.

Here’s what’s going on:

- When the locker is engaged, my compressor

$323 CKMA12 On-Board Air Compressor High Performance 12 Volt for Air Locker Differentials and Tire Inflation

CKMA12 (w/ARB solenoid & nylon air line) - will cycle approximately every 5 seconds
- Upon de-pressurizing the locker air line, a puff of gear oil will spray out of the solenoid exhaust port
- I can visibly confirm that air is entering the case by placing a balloon on my differential breather with the locker pressurized
- I’ve confirmed the appropriate amount of gear oil in the differential, so the O-Rings are sitting in an oil bath per ARBs specs.
- It happens irregardless of ambient temperature (Moab and snowy Washington)
- It was pressure tested immediately following installation, and held air without any leaks for 20 minute
- All internal O-Rings were replaced upon installation


All of these symptoms lead me to conclude that an internal O-Ring(s) has failed, causing the locker to pressurize the differential casing, and back flow through the air line…

It is in a relatively light duty application, with 4.88 gears and 255 tires. Hasn’t seen much hard usage.

Do you have any recommendations with regards to how I should rectify the issue? I’m located in Bellingham, WA - so driving to Renton is an option. However, I’ve done extensive work on my rig - and swapping the seals myself isn’t an issue. I realize that this model has been replaced with the

$1,091 RD129 Air Locking Differential

RD129; I’m hoping that you will still be able to support the older RD89s as well.

By the way, I’m a hardcore believer in ARB - your customer service is awesome.

Thanks,

 

Seems like there were some problem child ARBs way back when they were first released, seems as though most of the guys were taken care of. Either through a seal retrofit kit or an entirely new locker.

If I remember correctly, I did put PB Blaster directly into the port on the air inlet fitting (on the differential case), and that did help for some time. However, now that I've actually got gear oil exhausting through the solenoid - it's clear that the o-rings are shot.

Check your gear oil level in your diff. These style seals need a partial to full oil bath to function properly.

Check your differential breather. Make sure it's not plugged.

I'll let you know what ARB has to say. Their customer service has always been top-notch... I'm sure that they'll take care of me.

- Jake

 

Hmm... My compressor has always cycled about every 10 seconds but my locker has always worked other than one time and I had to blow the airlines clear as they were full of gear oil. I have the newer

$1,091 RD129 Air Locking Differential

RD129 locker though, not the RD89. Subbed to hear other people's experience and for responses from ARB.

I always assumed I just had an air leak at the solenoid and the oil in the lines was from my breather being faulty and the airline being the only source of relief for the pressure.

 

Almost all of the O-Ring issues have been centered around the older RD89.

I believe that ARB did an entire re-design on the seal structure for the

$1,091 RD129 Air Locking Differential

RD129.

That being said, a little mist of gear oil from your exhaust port on the solenoid seems to be normal for these lockers.

 

I'm glad that I'm not the only one. I bought mine used as well "with only 200 miles on it" but most of the parts were replaced anyway. I am anxious to see what they say. I may email them as well because the guy on the phone didn't act like he'd heard of these issues before. I'm not sure what would be the best solution to this. I dont want to pay for another install...

 

It's not just that particular model. I run mine with medical grade Nitrogen and have zero issues on the Taco. It is my understanding that humidity gets in the lines from the air compressor, condenses, and creates little expanding freeze plugs. The compressor pushes them down the line, gets up to PSI and shuts off, then pressure bleeds off around the ice kicking the comp back on. I also have ARB's in the FJ80, but for whatever reason oil barfs out of the diff into the lines and they don't freeze. I should probably fix that. My guess is the vent line is clogged... Edit: the taco on N2O doesn't have any oil in the lines at all. The FJ80 ran with an ARB compressor both front and rear spritz oil.

 

So I should check my diff breather? Is that the vent line you are talking about? Any other suggestions would be great. Thanks

 

Wait and see what ARB says. It wouldn't hurt to check the diff breather and make sure it's clear though.

 

Talked to ARB... They're backlogged for quite a while due to the holidays.

Basically wanted to make sure that they've seen my email, which they have. Mitch wasn't super confident that they'd be able to rectify the issue... A little bummed about that.

They've got a few emails to sift through, but I'm near the top of the list. At this point, it seems like I'll be getting a new seal kit in the mail. Which, might solve it - or might just be a band-aid. I might be in a position to send them my diff for a month or two to take apart...

I'll take a set of BP-51s as reconciliation.

 

Thanks for the update. I sent an email as well and haven't heard back yet.

 

These showed up in the mail this afternoon...

Kudos to ARB for prompt service.

Might have a chance to dig in to it this weekend; I'll update here as it progresses.

 

sweet

 

ARB replied to me and said they updated the design because of cold weather issues and are sending me new seals. I hope that works. Either way, great service so far. I'm guessing the guy who I talked to on the phone was new or hadn't heard of the issue before.