P/S Fluid Type and Seal Life

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I recently started rebuilding P/S Pumps due to availability issues and the skyrocketing cost of reman pumps. So far, I have rebuilt 4 or 5 Honda Power Steering Pumps and all of them had internal seals that were rock-hard. I don't know if this is a heat issue or if the Honda P/S fluid has inadequate seal conditions.

However, I rebuilt the P/S Pump in my FIL's Camry last week due to a seeping shaft seal. This was the first Toyota pump I had rebuilt. Aside from the seeping shaft seal, all of the other seals were soft and pliable. This system specified Dexron ATF. I think the FF was used from 0-75k, then Maxlife ATF for 30K, followed by Redline D6 for the last 30K.

Is it possible that ATF does a better job of keeping seals conditioned compared to P/S Fluid?
 
Am in the process of changing the p/s fluid in my Saab 9-3. It takes this type;
8403107FRO__ra_p.jpg
 
It's also possible that Honda pumps are more likely to run dry because you have to keep adding fluid them. The Honda fluid is also thicker than Dexron.

Honda requires a special fluid *and* they still have problems with their pumps! Just be glad their newer cars have EPS,which means no more special fluid :D
 
Honda takes special fluid. Maybe it's a crutch for bad seals? Maybe the car got neglected and regular fluid put in? Maybe there's a patent they need to avoid?
I did 4 or 5 Honda pumps. Same issue on each one, all were around 150K. It is either a seal material or fluid issue, not sure.
 
I recently started rebuilding P/S Pumps due to availability issues and the skyrocketing cost of reman pumps. So far, I have rebuilt 4 or 5 Honda Power Steering Pumps and all of them had internal seals that were rock-hard. I don't know if this is a heat issue or if the Honda P/S fluid has inadequate seal conditions.

However, I rebuilt the P/S Pump in my FIL's Camry last week due to a seeping shaft seal. This was the first Toyota pump I had rebuilt. Aside from the seeping shaft seal, all of the other seals were soft and pliable. This system specified Dexron ATF. I think the FF was used from 0-75k, then Maxlife ATF for 30K, followed by Redline D6 for the last 30K.

Is it possible that ATF does a better job of keeping seals conditioned compared to P/S Fluid?
Probably heat damage, try CHF (11S or 202 no matter) in one and see how it does. Are you priming the pumps with a drill or power ratchet after putting a seal kit in them? It is a good way to flush the fluid out also and prevents initial wear on the seals.
 
I did 4 or 5 Honda pumps. Same issue on each one, all were around 150K. It is either a seal material or fluid issue, not sure.
Curious:
What’s the probability those pumps had run for an extended time on other-than-Honda-brand p/s fluid?

One hears a lot that Honda fluids are ‘special,’ and while they’re certainly ‘different,’ chemically speaking, in many instances, I’m unsure whether that means they don’t survive well on aftermarket fluids.
 
On all my PS pumps, they all saw “synthetic” ATF - currently MaxLife but in the past Red Line D4 or M1. No leaks per my recollection.
 
I think the one in my Accord is coming up on rebuild time, maybe this summer. It's lived on Honda PSF its entire life so I'll see what the seals look like. Other than the suction side O-Ring it has never given me any problems in ~256k.
 
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I think the one in my Accord is coming up on rebuild time, maybe this summer. It's lived on Honda PSF its entire life so I'll see what the seals look like. Other than the suction side O-Ring it has never given me any problems in ~256k.
You could go on and do it during the holidays. ;) Enquiring minds want to know. LOL
 
I recently started rebuilding P/S Pumps due to availability issues and the skyrocketing cost of reman pumps. So far, I have rebuilt 4 or 5 Honda Power Steering Pumps and all of them had internal seals that were rock-hard. I don't know if this is a heat issue or if the Honda P/S fluid has inadequate seal conditions.

However, I rebuilt the P/S Pump in my FIL's Camry last week due to a seeping shaft seal. This was the first Toyota pump I had rebuilt. Aside from the seeping shaft seal, all of the other seals were soft and pliable. This system specified Dexron ATF. I think the FF was used from 0-75k, then Maxlife ATF for 30K, followed by Redline D6 for the last 30K.

Is it possible that ATF does a better job of keeping seals conditioned compared to P/S Fluid?
I read somewhere that seals made for hydraulic fluid (ex CHF11s) don't play nice with ATF however seals made for use with ATF play nice with hydraulic fluid.
 
I think the one in my Accord is coming up on rebuild time, maybe this summer. It's lived on Honda PSF its entire life so I'll see what the seals look like. Other than the suction side O-Ring it has never given me any problems in ~256k.
Over 3 years ago, I bought a new P/S pump for the '06 TSX from Amazon; don't think I paid more than $60.
I kept the original to rebuild it. Dang cheapo is still running like a champ.
 
Over 3 years ago, I bought a new P/S pump for the '06 TSX from Amazon; don't think I paid more than $60.
I kept the original to rebuild it. Dang cheapo is still running like a champ.
I can still rebuild it, if you want...
 
I recently started rebuilding P/S Pumps due to availability issues and the skyrocketing cost of reman pumps. So far, I have rebuilt 4 or 5 Honda Power Steering Pumps and all of them had internal seals that were rock-hard. I don't know if this is a heat issue or if the Honda P/S fluid has inadequate seal conditions.

However, I rebuilt the P/S Pump in my FIL's Camry last week due to a seeping shaft seal. This was the first Toyota pump I had rebuilt. Aside from the seeping shaft seal, all of the other seals were soft and pliable. This system specified Dexron ATF. I think the FF was used from 0-75k, then Maxlife ATF for 30K, followed by Redline D6 for the last 30K.

Is it possible that ATF does a better job of keeping seals conditioned compared to P/S Fluid?
I started supplementing the PS fluid in our 15 odyssey with lubegard ATF protectant. This should help to keep the seals pliable for many years.
 
Curious:
What’s the probability those pumps had run for an extended time on other-than-Honda-brand p/s fluid?

One hears a lot that Honda fluids are ‘special,’ and while they’re certainly ‘different,’ chemically speaking, in many instances, I’m unsure whether that means they don’t survive well on aftermarket fluids.
Honestly, not likely, at least for 2 of them.

I wonder if it is just a material issue. I doubt the rest of the car will last another 120-150k so we won't be able to see if the aftermarket seal kits fare any differently after the same amount of time.
 
Probably heat damage, try CHF (11S or 202 no matter) in one and see how it does. Are you priming the pumps with a drill or power ratchet after putting a seal kit in them? It is a good way to flush the fluid out also and prevents initial wear on the seals.

I switched my GM power steering pump to Pentosin CHF-11S at 56,000 miles. A lot of people I know have been using ACDelco Power Steering Fluid, and some use Dexron III. They have had issues with leaking pumps; I'm at 142,500 miles on the original pump.

I also have a Mitsubishi power steering pump that calls for Dexron III (H). I ran Motorcraft Mercon V in it since I did the first PSF flush and the original seals lasted 16 years and 285,825 miles before they started to leak. At this point, I replaced the seals with an OE kit from Mitsubishi, did a thorough flush and switched the system over to Pentosin CHF-11S. There was a definite improvement in steering feel, but it will be interesting to see how long these seals last.

I tend to flush out the PSP every 25,000 miles across the fleet, but have extended it to 50,000 miles with CHF-11S.
 
The O-rings in the ac fittings on japanese cars get hard and flat too. Must be the materials. Part of the reason why I always add a little bit of ester to every ac job.

I've started doing the same and noticed AC needing much less frequent recharging. So PAG doesn't swell or condition seals like POE does?

Castrol icematic sw100 is what I used
 
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