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93 4runner, 3.0 4x4, auto trans. I have a pin hole leak in my power steering, but I can't find anything that identifies the part. The part is mounted to the frame under the battery tray. All the PS hoses go into it from the pump and gear box. I can't seem to find any reference to it let alone get parts.
Anyone know what it is???
Seriously, though. If you asked a for-real mechanic that question, just like that, wouldn't you expect "I'm not sure, let me look at it"? At least post a photo.
A cooler sounds reasonable. I was thinking a pressure controller of some sort.
Your right a pic would help, but it is in a location that is very hard to see. There is the fender covering it from the wheel well and the battery tray covers it from the top and it's barely visible from the side if you could get a camera in there.. The other problem is I have never been able to get a pic to post on this forum.
As far as how a real mechanic would post it, well I have been a GM mechanic for 46years, specialize in Corvettes, I am ASE certified and I have an A&P license and a degree in aviation, Toyotas are just a recent thing and there is a defiant learning curve to get used to bad designs. I would hope the newer Toyotas are designed better than the old.
I have yet to see something like this on a power steering system. They are usually just a pump and a gear box and maybe a hydraulic slave assist.
I have looked through all of my Toyota manuals, the dealer and online and there is just no mention of this item.
I will try an get a pic where you can actually see at least part of it and try and get it to upload it.
It is defiantly fluid from the power steering unit. After four units whining I have switched to power steering fluid instead of ATF. The pump is working much better and no whine. I also changed all the hoses and flushed the unit. After flushing is when the leak started, although nothing was done to the unit in question. Here are the best picks I can get. one top and one side. This is all you can see of the unit unless everything above, below and to the side are removed.
Well, If it's not what I sent in the picture, then I have to agree with "scope103"
Anti Lock Brake Actuator, not in a fun location, I believe there should also be some brake lines going to it also.
Take a gander at scopes link again.
Thanks, ksti, I felt like I was just talking to myself.
Toyota clearly specifies that the PS pump uses ATF only. Several on this site have expressed the belief that their pump leakage was caused by using "power steering" fluid instead. Like the rest of us, I don't have any way to know if using the wrong fluid really does cause leaks.
It is defiantly fluid from the power steering unit. After four units whining I have switched to power steering fluid instead of ATF. The pump is working much better and no whine. I also changed all the hoses and flushed the unit. After flushing is when the leak started
What did you flush it with?
Also ATF should not cause a pump to whine unless level was to low
causing air bubbles (foam).
Sounds like 4 bad units right out of the box, 5th one worked, but for how long.
Strange, I replaced my pump and had whining with ATF as well. PS fluid fixed it. ...5 years ago
If the leak is at the actuator, you have Toyotas first truck anti lock rear brake system. It takes full control of the rear brakes and cycles (engages) the rear shoes ~30 times a second preventing lockup. Pressure is provided by the PS pump. A sensor in the rear pumpkin detects if lockup has occurred and engages the system. When in 4WD the ABS is turned off.
I could be an actuator. The rear brakes have a load compensating system on them and even though there are no other signs of an ABS system when getting parts is uses the parts listed for ABS. Your right it is very tough to get too. I think this may have solved the question.
I will say the PS pump is working the best it ever has using the PS fluid and I think I will stick with that.
I will see what I can find for part for the ABS. Knowing what it is should help with parts.
Thanks for your input, who would have know?
I could be an actuator. The rear brakes have a load compensating system ...
The LSPV and Rear-Wheel Antilock are two completely different systems. Other than the fact that they are both part of "brakes," they have nothing to do with each other.
Originally Posted by pplusent
... Thanks for your input, who would have know?
That's why I provided the pages of the Factory Service Manual. When it comes down to "something I read on the internet by a guy who says he's a certified mechanic" versus the Manual, I know which one I follow.
The Brake Actuator is right below the power steering pump, and gravity pulls all fluids downhill. Considering that the Brake Actuator is just shy of a $Grand, https://parts.lakelandtoyota.com/p/T...451035030.html I would want to be VERY sure the power steering pump wasn't leaking onto it. Particularly since you've been running "power steering" fluid.
If you are not sure if you have a ABS actuator, Check the top of the rear pumpkin, If wires are coming out of the top you have the ABS system on your truck.
It turns out it is the actuator leaking. I can see the fluid coming out every time I clean it. I have only been able to find a replacement part, but no rebuild kit. The part is a dealer part and from what I can see it is only on the 93's and cost $1400.00. I think I will rebuild it and just make gaskets if needed.
Don't mind rebuilding it I am just going to hate getting it out. Oh well, nothing new there!
Thanks all!
The LSPV and Rear-Wheel Antilock are two completely different systems. Other than the fact that they are both part of "brakes," they have nothing to do with each other.
That's why I provided the pages of the Factory Service Manual. When it comes down to "something I read on the internet by a guy who says he's a certified mechanic" versus the Manual, I know which one I follow.
The Brake Actuator is right below the power steering pump, and gravity pulls all fluids downhill. Considering that the Brake Actuator is just shy of a $Grand, https://parts.lakelandtoyota.com/p/T...451035030.html I would want to be VERY sure the power steering pump wasn't leaking onto it. Particularly since you've been running "power steering" fluid.
Good luck!
The problem was it did not show up in the manuals under power steering system. I wasn't aware of this system on the vehicle and have not seen it on other 4runners. And yes I am a certified GM mechanic and I am new to Toyotas. I only have a Toyota because of it's size. I do a lot of driving down narrow washes here in Arizona.
final fix. It was the actuator, but upon further research it turns out to be a common problem due to a defective design. I have included pics. The fixed metal return line has a single o-ring that seals it which would be ok if there were two bolts too secure it in place. As it turns out there is only one bolt securing one side of it. What happens is, if you replace the rubber hose it allows the mount to move which unseats the o-ring and causes a leak. Also if it is jarred in any way it will also leak. You will notice the one pic is a newer model where they have added a bolt. When replacing the O-ring I would recommend using a good sealer on the base to create a gasket just in case. I use Toyotas ATF resistant RTV and it works well, but expensive at 26 bucks a tube. Permatex also makes a similar ATF RTV that is very similar and works at 3 bucks a tube. I have also had good luck with the permatex "the right stuff".
I hope the info help someone in the future!
Thank for the input.
For what it's worth, o-ring seals are commonly held with a single bolt. As long as the o-ring doesn't pull all the way out of the bore it still seals. Your high-pressure lines to the a/c compressor are held with single bolts. The a/c compressor lines (flexible) are subject to a lot of vibration, and don't leak. I doubt your moving the power steering pressure line, alone, contributed to your leak. It's designed to handle that. And in your case, the leak was in the low-pressure line (as evidenced by the screw-type hose clamp).
But it's good you found it, and fixed it efficiently. Thanks for sharing with us.
10-17-2017, 10:46 PM
