Early '91 4Runner power steering gearbox leak - options to solve?

Thanks for your help! I have this small but persistent leak coming from the top-seal on the power steering gearbox where the steering wheel linkage attaches (see photo). Looking for input on how best to resolve.

Options I'm aware of:
- replace with rebuilt gearbox
- replace with new non-Toyota gearbox (gearbox no longer available from Toyota)
- rebuild kit and replace just the seal in question.

I don't believe I have the skill to do a full gearbox rebuild. But I watched a video where a guy changed just this seal on a Gen-1, and that looked doable.

Appreciate input from others regarding. Looking for a reliable long-term repair.

Again Thanks,
Randy Graves
CdA, ID




91 4Runner Power Steering Gearbox Leak

 

There's also Option 4: Roll the dice on a junkyard gearbox that looks functional. I have the same issue and that's how im gonna try to resolve it. Cheaper than option 1 and 2, far less work intensive than option 3

 

I recently rebuilt mine. I did not replace the seal where yours is leaking but the rebuild process is cheap and straightforward. I was very pleased with the results. Here’s my post about it.
https://www.yotatech.com/forums/f116...an-too-314012/

 

Melrose,

Thank you for your reply and link to your steering gearbox rebuild tutorial - Excellent Tutorial! I don't know how I missed this in my searching. My current "plan" is to order the rebuild kit and just change the input shaft bushing/seal referencing this video
The gearbox in your tutorial looks the same as mine (early '91). One thing you mentioned that I don't understand is: disconnecting the steering linkage at the rag bolts rather than removing the bolt at the gearbox input shaft spline. In your 1st picture I see what I believe are the rag bots (?) but it looks like there are studs on the other end. Can you elaborate a bit on this?

Again Thanks, I appreciate your reply and all the work you put into making your tutorial.

Best Regards from N. Idaho,
Randy Graves

 

There are two bolts/nuts on the rag joint. If you remove them it is easier than removing the one bolt on the input shaft clamp and trying to slide the clamp off the splined shaft. It is easier to reassemble also and easier to locate the clamp back onto the splines while on the bench, instead of in the engine compartment. Also having the rag joint in hand while rebuilding the box allows you to rotate the input shaft easily to test for smooth and full movement.

you may as well reseal the whole box. It really does make a difference. I suspect because with worn orings inside it may not be at optimal pressure.

 

Melrose, Thank You for the rag joint further explanation - makes sense now. Rebuild kit on order. Plan to tackle the job next weekend. Will give careful thought to a full rebuild vs just replacing the input shaft seal. The steering itself is pretty solid, maybe just a tad of play. But want to get this leak fixed. We've had our '91 since new and never really off-roaded or driven hard. It is my wife's vehicle and our shared winter vehicle. I tow a sailboat with it around the Pacific NW. Just now approaching 200K miles. Couldn't ask for a better rig!

I appreciate your time and help - Thank You!

Have a Great Weekend,
Randy Graves
CdA, Idaho

 

I'm not a fan of additives but years ago my 91 4Runner had a small leak similar to yours. I drained and replaced the PS fluid with Lucas Stop Leak (goldish bottle) and it's been leak free ever since. It worked so good that when I bought my 2001 4WD Sequoia, while still new, I did the same process and never had a leak! BTW, I still have both vehicles and neither one leaks so you might try this before tearing into the unit. It swells the seals and they stop leaking.

 

Sequoia'd, I want to Thank You for your reply. Being that you are speaking from personal experience I want to look into this further (I'm also not a fan of Stop Leak products). I can't identify a Lucas Stop Leak in a goldish bottle. Any other details? Did your run the Lucas only or did you add it to fresh Dextron II/III

Any other information you can provide would be appreciated.

Again Thanks,
Randy Graves
'91 4Runner
N. Idaho

 

Randy, let me look around in the shop and see if I still have some. As for the application, I drained the reservoir leaving the box alone. then added the stop leak to the normal level. so if I was to guess, I would say it's probably a 50/50 mixture..... whatever it is, it works. Since it has a component that keeps the seals more pliable, they don't take a "set" and wear in a particular spot or worse, shrink with age. I was so impressed I wondered why the manufacture does not use it as a normal fill.

Will it work for you? Don't know. All depends if the seals are too far gone but it can't hurt and the price and labor is a lot less than a rebuild.

EDITED: I was mistaken on the name. I found the bottle and it is Golden Eagle "No Leak" Here's a link so you can see the product.

https://www.acehardware.com/departme...cation_All_All

Good Luck!

 

Sequoia'd, Thank You!

Another Question - On your 4Runner does the power steering pump also provide fluid to the 2-wheel ABS System? If so, did you have any concerns with the Stop-Leak affecting the ABS box?

Again Thanks & Best Regards,
Randy Graves
N. Idaho
'91 4Runner SR5 5-spd 4wd

 

Try a salvage unit. I bought/returned 3 aftermarket PSG boxes for my 86 2WD. None of the input shafts would accept the rag joint fitting. So, I searched an online salvage for a Toyota PSG box and found one for $98 shipped from WA State to VA. Input shaft fit perfect. The aftermarket crap units where $180 to $225. It's been 7 years now and still no leaks and working like day one
.

 

Not that I know of! I have the automatic w/overdrive rather than the manual. Never had any problems with the ABS or brake system except the normal wear and tear. On the '91 I was not aware there is a connection with the PS and ABS..... learn something everyday!

FYI, the NO LEAK is just a petroleum based product with seal conditioners so if it does come in contact with brake components,there probably is no issue. Also, keep in mind it's not a coagulator, just a conditioner. Hope this helps!

 

It's pretty much the same as a little shot of diesel. Swells the gaskets. Works like a dream on minor oil leaks, I have found. Just until you can replace the seals in question, honestly, but it works real good for that.

I doubt they're so crass as to actually use diesel, but it's similar. Swells the gaskets, stops the minor leaks. Probably works as well as diesel, maybe better.

Good luck!
Pat☺

 

Thanks Everyone for Your Input and Help - I Greatly Appreciate it! I'm still gathering information as to how best to proceed. I emailed Lucas asking if it's safe to use their stop-leak product in a system running Dextron II/III that also pumps the power steering fluid to the rear-wheel ABS actuator. They responded that it is safe to use their stop leak in such a situation. I've also received the power steering gear box rebuild kit, and also have a new Lares ps gearbox due to arrive tomorrow, as a plan-b should I not be able to rebuild the original. At this point I'm thinking a rebuild/replace is a better long term solution than stop-leak.

In preparation repair/replace the ps gearbox I pulled the pitman arm and read through the FSM and Chilton's and ran into a snag.

The Chilton's reads: "If any of the lines or components in the power steering system are loosened or removed, the brake system must be bled as well. Preliminary bleeding of both the power steering and brake systems will eliminate most of the air, but the vehicle MUST be taken to a dealer to have the systems properly bled using the Toyota ABS Checker. Be warned that until this is done, the rear wheel anti-lock brake function may be impaired" . I've contacted my local dealer to see if they can do this test & bleed, and the cost. Waiting to hear back regarding.

QUESTION: Has anyone run into needing a special Toyota ABS checker when repairing the power steering system on a vehicle with rear-wheel-antil-lock (RWAL) brakes?

Thank So Much!
Randy Graves
Coeur d'Alene, ID
early '91 4Runner SR5, 3VZ-E, 5spd, 195K miles

 

Hello RKGRAVES, how did you solve the issue with the PS bleeding? Did you have to take it to the dealer for the special ABS checker tool?

 

​​​​​​​I don't recall this. Curious what the FSM says

 

This is what the Toyota repair manual says
​​​​​​​

 

Red91runner,
I did not take it to the dealer for the repair/bleed. I called the Dealer and they were vary vague on the cost, estimating between $600-$1200. I talked with a local shop and they quoted me $600, and that was with them installing the part, but they did have or know of the special ABS tool. I called Lucas and talked with them about using their "stop-leak" additive/fluid in the system and they were confident it wouldn't introduce any problems.

In the end I sucked out old fluid and replaced it with new, best I could, and oddly enough that reduced the leaking. I then decided I could live with the now-minimal leak vs the cost & risk of a more permanent repair.

This was a couple of years ago and the leak has remained minimal, a few drops after a drive; more so when it is hot outside. This is my wife's ride and it only sees a few thousand miles a year.

Hope this helps! And Best-Of-Success on your repair.
Randy Graves
Coeur d'Alene, ID

 

Thank you Randy for the explanation. I couldn’t believe the dealer would charge that much. Once I finish with my repairs I am going to try find a shop that has this tool. Somehow I missed the bleeding procedure for the rear antilock in the FSM. I bought parts and took it apart to repair the steering gear box and now it is too late. I guess what you did was wise. For these kind of old vehicles there is no need to spend so much money, I would have lived with a leaky gear box