Is the Non-Comp ARB for Ford 9" Really That Weak?

[Sean]

Is the non-comp version of the ARB for the Ford 9" really so failure prone that spending roughly 3X more on the comp version the best solution?

I'm not a racer and don't compete and these 3rds would be going in JHF portal equipped axles so the 3rds should see a lot less stress. I'm a firm believer in buy once, cry once.....but should I be considering spending that much extra when ECGS has a 5 year warranty on the regular ARB 9" 3rds?

 

[Tech Tim]

Is the comp version that much stronger? Yes. Anyone doing the go fast stuff or rock racing or bouncing of any sort, then yes, spend the extra $$ for the comp version.... buy once, cry once.

Do you need it if you're building a crawler? I'd say no. But take a few extra precautions.

Bump the air pressure up to 150psi if running ARB solenoids, bump it up to 200-250 if you are running air switches.

Do good air tube management inside the diff, keep the line from getting pinch down.

If you can find a chromo locking collar for it, swap that in too.

 

[Sean]

Is the comp version that much stronger? Yes. Anyone doing the go fast stuff or rock racing or bouncing of any sort, then yes, spend the extra $$ for the comp version.... buy once, cry once.

Do you need it if you're building a crawler? I'd say no. But take a few extra precautions.

Bump the air pressure up to 150psi if running ARB solenoids, bump it up to 200-250 if you are running air switches.

Do good air tube management inside the diff, keep the line from getting pinch down.

If you can find a chromo locking collar for it, swap that in too.

Thanks for the input.

Can you explain the logic in the higher air pressure? I've run air switches in the past and in my current car and the front is currently set at 95 PSI and I've never had a problem with it. Just wondering the reasoning....IIRC, ARB recommended not going over 95 PSI way back when....

 

[AgitatedPancake]

Thanks for the input.

Can you explain the logic in the higher air pressure? I've run air switches in the past and in my current car and the front is currently set at 95 PSI and I've never had a problem with it. Just wondering the reasoning....IIRC, ARB recommended not going over 95 PSI way back when....

I'm not one to speak on the strength of the standard ARB vs the comp option, but IIRC the logic behind the extra air pressure is - for the locking collar to skip teeth, it has to overcome the air pressure pushing it inward so more pressure = more insurance that it will stay engaged. Probably not a huge deal with nice sharp teeth with crisp corners, but as it gets any wear from crash locks or previous slippage and the corners round down, there's going to be more and more force trying to lever the lock collar outward against the locking air pressure.

 

[Tech Tim]

That had to have been way back..... Back in my day at ARB ('97 to 06), we were having rock crawl competitors running up to 300 psi without any issues.

EDIT AP beat me to it.....
The RD99s have very little locking collar engagement. The more pressure you can lock that collar in place with, the better it will hold.

2nd EDIT:
Back in my day at ARB ('97 to 06)

Dang, it's been 17 years since I was at ARB.... I'm getting to be a dinosaur!

 

[Sean]

That had to have been way back..... Back in my day at ARB ('97 to 06), we were having rock crawl competitors running up to 300 psi without any issues.

EDIT AP beat me to it.....
The RD99s have very little locking collar engagement. The more pressure you can lock that collar in place with, the better it will hold.



Dang, it's been 17 years since I was at ARB.... I'm getting to be a dinosaur!

This was more like 2003 or so.....I specifically remember the 95 PSI....but not sure why, so it's entirely likely I'm wrong.

 

[Sean]

That had to have been way back..... Back in my day at ARB ('97 to 06), we were having rock crawl competitors running up to 300 psi without any issues.

EDIT AP beat me to it.....
The RD99s have very little locking collar engagement. The more pressure you can lock that collar in place with, the better it will hold.



Dang, it's been 17 years since I was at ARB.... I'm getting to be a dinosaur!

I assume the comp version is similarly limited in terms of the design's locking collar engagement and would wager it's just better materials? In other words, with air switches and the comp version, you'd still recommend 200-250 PSI? Or...are the comp version's default position "locked" (and so the point is moot) like the comp Zip lockers were?

 

[Weasel]

huh I thought seals were the reason for the 95psi. My limited experience blew 2 seals and thought it was from 110-125 psi.

 

[Tech Tim]

I assume the comp version is similarly limited in terms of the design's locking collar engagement and would wager it's just better materials? In other words, with air switches and the comp version, you'd still recommend 200-250 PSI? Or...are the comp version's default position "locked" (and so the point is moot) like the comp Zip lockers were?

huh I thought seals were the reason for the 95psi. My limited experience blew 2 seals and thought it was from 110-125 psi.

In testing we've ran the seals up to 300 psi without any blow-outs.

The ARB twin compressor has a 150psi pressure switch in it stock, so they are officially ok with that pressure.

I'd recommend a minimum of 150psi on any Air Locker. For a comp application, I'd recommend 200+psi.

 

[Tech Tim]

Huh? I’m asking about the RD99CE vs the RD249CE.

That was read too fast smart ass reply..... .

Does the 35 spline competition edition require a 3.812” case or does that only apply to the 40 spline version?

Huh? I’m asking about the RD99CE vs the RD249CE.

The RD99CE is 35 spline and will fit in a 3.25" case.

 

[reptillikus]

This was more like 2003 or so.....I specifically remember the 95 PSI....but not sure why, so it's entirely likely I'm wrong.

That's what I thought too, and I got mine back in 05, so around the same time as you.

In testing we've ran the seals up to 300 psi without any blow-outs.

The ARB twin compressor has a 150psi pressure switch in it stock, so they are officially ok with that pressure.

I'd recommend a minimum of 150psi on any Air Locker. For a comp application, I'd recommend 200+psi.

That's interesting, I guess I'll turn mine up a bit before my next trip.

 

[white-rhino]

RE 9" non comp ARB's, I've run them in 2 different rigs with tire size ranging from 35 to 39 stickies powered by Chevy v8's. Didn't have any issues.

RE air pressure, I'm running the single cylinder compressor on my 14 bolt ARB and the dual cylinder compressor in my JK. I didn't realize the pressure was adjustable. Being lazy without looking, how is this done?

 

[Sean]

huh I thought seals were the reason for the 95psi. My limited experience blew 2 seals and thought it was from 110-125 psi.

As I recall...that was what I was told as well....but thinking back, it may have been Shannon Campbell recommending that, not ARB. I honestly don't recall now.

 

[Sean]

In testing we've ran the seals up to 300 psi without any blow-outs.

The ARB twin compressor has a 150psi pressure switch in it stock, so they are officially ok with that pressure.

I'd recommend a minimum of 150psi on any Air Locker. For a comp application, I'd recommend 200+psi.

Thanks for the clarification....

I really appreciate your help....you helped me way back when on the old board too. Much respect, Tim.

 

[Sean]

RE 9" non comp ARB's, I've run them in 2 different rigs with tire size ranging from 35 to 39 stickies powered by Chevy v8's. Didn't have any issues.

RE air pressure, I'm running the single cylinder compressor on my 14 bolt ARB and the dual cylinder compressor in my JK. I didn't realize the pressure was adjustable. Being lazy without looking, how is this done?

and I've run them mostly in D60s (and some Toyota 8" back in the day) with 40s.....I've heard the shape of the 9" makes them weaker....I wonder if that comes into play here.....

 

[Tech Tim]

Back at you...


FYI - You can buy those 150 psi switches for ARB or other sources to add the the ARB medium compressor or even a different brand comp. to bring pressures up to 150psi.

Every ARB I've ran or set-up in the past 15-20~ish years, have gotten the 150 psi pressure switch (at minimum) and we've have never had any sort of seal failure for over-pressurizing.

I would not recommend one of the mini ARB compressors or any other mini compressor unless you were to add in a small reservoir tank.

 

[YotaAtieToo]

So you just replace the pressure switch with any 150 psi switch?

Only arb I currently have is a 7.5 clamshell, but I still want to keep odds in my favor.

 

[Tech Tim]

and I've run them mostly in D60s (and some Toyota 8" back in the day) with 40s.....I've heard the shape of the 9" makes them weaker....I wonder if that comes into play here.....

The shape of the 9" makes it very strong, the gears are fairly small for the abuse they get and they hold together.

The biggest problem with the RD99 is the locking collar engagement. It is somewhere around 3/16". There is a thread or two on the old board showing the engagement and what people had done to give it a little more engagement and make it stronger.

As mentioned above, with that shallow engagement, you want a lot of air pressure holding it locked in.

I really don't know much more about the RD99CE or the RD249CE, those both came into production after I got out of the racing scene. One of these days I'll get one in my grubby paws and do a deeper dive.

FWIW - The reason you want to stay around 150psi when using the ARB solenoids is they start lifting their valves off the seats around 170psi and will leak air, so 150psi max on the ARB solenoids.

 

[Tech Tim]

So you just replace the pressure switch with any 150 psi switch?

Only arb I currently have is a 7.5 clamshell, but I still want to keep odds in my favor.

Yes, use ARB part #180901, they are fairly inexpensive, iirc $15-16.

You can get 150 psi pressure switches on Amazon for around the same amount.

1/4" NPT if you are retrofitting into an ARB compressor.

 

[Sean]

Back at you...


FYI - You can buy those 150 psi switches for ARB or other sources to add the the ARB medium compressor or even a different brand comp. to bring pressures up to 150psi.

Every ARB I've ran or set-up in the past 15-20~ish years, have gotten the 150 psi pressure switch (at minimum) and we've have never had any sort of seal failure for over-pressurizing.

I would not recommend one of the mini ARB compressors or any other mini compressor unless you were to add in a small reservoir tank.

I trust you completely on the 150-250 PSI (depending on the switches obviously). I'm running a really old ARB single cylinder compressor (just for the locker) in my current buggy.I haven't had any issues with it other than vibration occasionally (like once in a decade) loosening the tank and the o-ring leaking. Should I be rethinking using this compressor?

 

[white-rhino]

Back at you...


FYI - You can buy those 150 psi switches for ARB or other sources to add the the ARB medium compressor or even a different brand comp. to bring pressures up to 150psi.

Every ARB I've ran or set-up in the past 15-20~ish years, have gotten the 150 psi pressure switch (at minimum) and we've have never had any sort of seal failure for over-pressurizing.

I would not recommend one of the mini ARB compressors or any other mini compressor unless you were to add in a small reservoir tank.

So what PSI is the stock ARB set at?

My JK has ARB's front and rear and has the dual cylinder compressor. We have used it a few times to air up tires that are dangerously low, not to re-air to street pressure. (burped a tire or someone let too much air out) I'm amazed at how good that compressor works.

I have the single cyl ARB compressor for my 14 bolt. It's only intended purpose is to fire the locker. But, I have used it to air up a low tire on a VERY rare occurrence. I have thought about adding a small surge tank for the occasional die grinder trail repair. I have one that is about a quart or liter in size that would at least give a little burst of grinding capability.

 

[Tech Tim]

I trust you completely on the 150-250 PSI (depending on the switches obviously). I'm running a really old ARB single cylinder compressor (just for the locker) in my current buggy.I haven't had any issues with it other than vibration occasionally (like once in a decade) loosening the tank and the o-ring leaking. Should I be rethinking using this compressor?

The is the old RDCKA- single:

This is the newer CKMA12 -single:

Both are good compressors to run. I have an old RDCKA that still runs good after 20-ish years. Granted I haven't hammered it, overheating it from filling too many tires, etc.

This is the mini (pn#CKSA12):

IMO Do not run this one with dual locker without running a small reservoir at the far end of the system. I did run one for years in my old LT IFS 4Runner and never had an issue. But, I did install the ARB manifold as a mini reservoir.

It runs the same 100psi pressure switch as the medium single compressor (CKMA12).

Do not use this one to fill tires.

This is the ARB manifold - These are small and can be mounted close to your axles to get a larger supply of air faster:

So what PSI is the stock ARB set at?

That depends on whether it is the single or the twin. Unless they've changed something, the single is getting a 100psi pressure switch pn# CO35 (on at 70 - off at 100) and the twin is getting a 150psi switch pn#180901 (on at 135 - off at 150psi). The switches look the same, just different pressure ratings.

My JK has ARB's front and rear and has the dual cylinder compressor. We have used it a few times to air up tires that are dangerously low, not to re-air to street pressure. (burped a tire or someone let too much air out) I'm amazed at how good that compressor works.

If you have a twin compressor feel free to use the hell out of it. They are rated for 100% duty cycle and I'll use them to go from single digits up to street pressures without concern.

I have the single cyl ARB compressor for my 14 bolt. It's only intended purpose is to fire the locker. But, I have used it to air up a low tire on a VERY rare occurrence. I have thought about adding a small surge tank for the occasional die grinder trail repair. I have one that is about a quart or liter in size that would at least give a little burst of grinding capability.

If it is the mini, definitely do not use it to fill tires.

If it is the medium, you can use it to fill tires, but it has a 50% duty cycle - 30 mins on-30 mins off.

There are other good compressors out there too. Just make sure you get good clean air to feed your air lockers (and tires).

 

[YotaAtieToo]

The is the old RDCKA- single:

This is the newer CKMA12 -single:

Both are good compressors to run. I have an old RDCKA that still runs good after 20-ish years. Granted I haven't hammered it, overheating it from filling too many tires, etc.

This is the mini (pn#CKSA12):

IMO Do not run this one with dual locker without running a small reservoir at the far end of the system. I did run one for years in my old LT IFS 4Runner and never had an issue. But, I did install the ARB manifold as a mini reservoir.

It runs the same 100psi pressure switch as the medium single compressor (CKMA12).

Do not use this one to fill tires.

This is the ARB manifold - These are small and can be mounted close to your axles to get a larger supply of air faster:

That depends on whether it is the single or the twin. Unless they've changed something, the single is getting a 100psi pressure switch pn# CO35 (on at 70 - off at 100) and the twin is getting a 150psi switch pn#180901 (on at 135 - off at 150psi). The switches look the same, just different pressure ratings.



If you have a twin compressor feel free to use the hell out of it. They are rated for 100% duty cycle and I'll use them to go from single digits up to street pressures without concern.



If it is the mini, definitely do not use it to fill tires.

If it is the medium, you can use it to fill tires, but it has a 50% duty cycle - 30 mins on-30 mins off.

There are other good compressors out there too. Just make sure you get good clean air to feed your air lockers (and tires).

Good to know. I run the medium/single. But they're only 35x10.5s, so it's about 30 mins to air up anyway.

 

[white-rhino]

Looks like I have the CKMA12 -single on the buggy. I just ran out to the shop but it’s up on the hoost over my head. Best pic I could get.

I have no intention to use it to fill 42” tires on a regular basis but if it’s needed to get back to the tow rig …..

 

[Sean]

The is the old RDCKA- single:

This is the newer CKMA12 -single:

Both are good compressors to run. I have an old RDCKA that still runs good after 20-ish years. Granted I haven't hammered it, overheating it from filling too many tires, etc.

This is the mini (pn#CKSA12):

IMO Do not run this one with dual locker without running a small reservoir at the far end of the system. I did run one for years in my old LT IFS 4Runner and never had an issue. But, I did install the ARB manifold as a mini reservoir.

It runs the same 100psi pressure switch as the medium single compressor (CKMA12).

Do not use this one to fill tires.

This is the ARB manifold - These are small and can be mounted close to your axles to get a larger supply of air faster:

That depends on whether it is the single or the twin. Unless they've changed something, the single is getting a 100psi pressure switch pn# CO35 (on at 70 - off at 100) and the twin is getting a 150psi switch pn#180901 (on at 135 - off at 150psi). The switches look the same, just different pressure ratings.



If you have a twin compressor feel free to use the hell out of it. They are rated for 100% duty cycle and I'll use them to go from single digits up to street pressures without concern.



If it is the mini, definitely do not use it to fill tires.

If it is the medium, you can use it to fill tires, but it has a 50% duty cycle - 30 mins on-30 mins off.

There are other good compressors out there too. Just make sure you get good clean air to feed your air lockers (and tires).

Yep, I have the RDCKA. Great tech as always! I'll get the 180901 switch to replace the CO35. As I said, I only use it for the front locker....I'm on a trailer so I rarely need to use my OBA....which is a Toyota A/C pump engine driven and dedicated to the purpose with a 5 gallon tank under the cargo area for tire filling duty or air tools. I've got a port in the tank set up to take the ARB air line if needed if the ARB compressor takes a shit.

 

[Sean]

Tech Tim Does Northridge not carry that part (the ARB 180901 150 PSI pressure switch)? Can't seem to find it on the site (and I think I read you're working there now).....would rather give you the business than 4WP or Summit.....

 

[Tech Tim]

Tech Tim Does Northridge not carry that part (the ARB 180901 150 PSI pressure switch)? Can't seem to find it on the site (and I think I read you're working there now).....would rather give you the business than 4WP or Summit.....

Just checked and we don't, that's weird. I'll get them to add it (or add it beck?) to the site.

 

[Tech Tim]

I've got a port in the tank set up to take the ARB air line if needed if the ARB compressor takes a shit.

That's a great back-up plan.

 

[Sean]

Just checked and we don't, that's weird. I'll get them to add it (or add it beck?) to the site.

Thanks....I'll keep checking.

 

[Sean]

That's a great back-up plan.

2 is one, one is none. ;)