pplusent

93 4Runner 3.0. Three weeks ago I yanked out the awful A340H transmission and replaced it with a manual 5 speed trans. The A340H kept overheating then coming up 2 qt low on fluid. Now with the manual in there it has come up one quart low on gear oil. On the bench I set it up with the three and a quarter quarts of gear oil then installed the tranny. After installation I checked the oil and it was full, but 1000 miles plus later it is low a quart. There are no external leaks visible anywhere and no drips. A quart of oil is a lot and should easily be seen somewhere! So where could the oil have gone? all vent are dry as well.
Also the clutch master cylinder fluid level drops 3/8 every week, but no external fluid anywhere and the clutch is working fine! I just don't understand these 4runners and their fluid loss. There has to be some secret place where it all goes kind of like sock that go missing in the laundry!
Anyone know where this secret place is?

RJR

As far as the transmission fluid goes, check your transfer case. There is supposed to be a seal between the tranny and tcase, but if that fails, the tranny oil can leak back into the tcase, overfilling it. Since the two are bolted tightly together, this won't show up as an external leak.

Can't help you on the clutch MC off the top of my head.

pplusent

Yes that crossed my mind. I used all Toyota seals at great expense and so far two have failed. Will never use their seals again. I can't imagine the chamber being full of oil will hurt anything. The fluid can't get into the transfer case due to the seal on that shaft. There are two seals in there one on the transfer case and one on the tranny case which is a Toyota seal. Maybe it will act as a reserve when going down hill. LOL
If you know of any problems this can cause please let me know.
Thanks for the input

keycw

as far as seal quality, I would respectfully disagree that you will find any aftermarket seal of better quality (as far as off the shelf parts go). marlin is making some pretty good heavy duty seals now, which I have in mine. installation can have everything to do with how well they hold up, im not making a jab at you im just making the statement that seal installation and longevity are directly related. if your loosing fluid from your master cylinder at a rate of 3/8" a week its coming out somewhere.. id check under the carpet. the other option is that the cylinder wasn't bench bled and its working out air over time, possibly.

pplusent

The clutch cylinder was bench blead, but it is the second one. The first cylinder leaked badly under the reservoir. I have checked the interior side of the cylinder and it is dry as well as all the connection points and no fluid anywhere. I have manually bled the system, and also vacuum bled the system. If there is air in it I don't know where it is hiding.
As far as the seals, I haven't had issues with the Toyota seals until these. The installation was perfect with no issues and I pre checked all of them for fit before installation. In retrospect I have never had an aftermarket seal fail in 50 years as a mechanic. Although I was always a GM mechanic, RV mechanic, and licensed aircraft mechanic. Toyotas are new to me and can quite a bit of a challenge to get used too design wise. The seals seem to never be the right ones the first time from Toyota. You always have to measure them, it is rarely cut and dry due to model variations.
I have restored This 4runner from the ground up. Mechanically there are no parts left that have not been replace or rebuilt using both aftermarket, or Toyota parts. There are no external leaks any where except for the axel leak on the passenger side in front, but it is about a drop a month and that is one of the Toyota seals.
I suppose it is always possible the rear trans seal caught an edge on installation of the transfer case, but the T-case was installed on the bench and would be rare to have an issue with that. I won't pull the seal unless anyone knows of a reason that the failed seal will damage anything. If there is a problem I will pull the T-case and change all the seals in the T-case as well. I still have to return all $75 worth of T-case seals I still have from Toyota: not one of them were the right size so I still have the original seals in the T-case and they are not leaking.
I have finally got this 4runner working well and I am extremely happy with it's performance now. The Raptor 198 HP 3.0 V6 is awesome at 22 MPG city, but still only 14 MPG highway due to the 4:88 gears, but that should change when I replace my next set of tires with 33's. The new Aussie locker works like a charm and seems to climb just about anything. The three inch lift was a great change in the suspension. I did a 3 inch under ball lift, but only raised it 1" so I could back off the torsion bars. The suspension actually articulates now unlike before where it was so stiff it didn't absorb any road shock at all. The manual trans swap increased performance 10 fold over the awful A340H trans. The upgraded radiator fixed all the cooling issues the stock configuration had and that is a big, big deal hear in Arizona. The new AC system also finally working well and cooling to 38 degrees, also a Big, Big deal here.
Next months upgrades will be a short throw shifter and rear disk brakes.
I use this vehicle off-road on the average of three days a week half of the year, so reliability and performance is vital. The 4runner was the only truck I could find narrow enough to get down the washes and passages to access our gold mine and haul all my equipment inside. In it's original configuration it was not much use at all, but with the improvements it has become an excellent off road asset. Just have to get these two items sealing right and the final upgrades and it will be perfect.

keycw

dealerships can be tricky, might want to start using the lakeside Toyota overstock website for parts, a lot of people like it, myself included.

pplusent

Thanks I will bookmark that and keep them in mind next time. Nothing I hate worse then having to redo a job because of a bad part.

ev13wt

I don't know how, but the oil travels.
People have built overflow pipes from tcase to tranny.

old87yota

When ordering Toyota parts, use the Vehicle Identification Number (VIN).

Toyota's electronic parts catalog is set up in such a way where when the VIN is used, only the parts that actually fit that particular vehicle should show up to order and takes much of the guess work out of the process.

Now if you are modifying your truck and changing components from other trucks to yours that the truck did not originally come with, it can be challenging to find the exact part you need as Toyota's parts catalog will not show parts that your truck did not originally come with when using the VIN or it will show a bunch of parts that could fit your truck based on year and model without the VIN.

Toyota set up their parts catalog for easy original direct replacement parts ordering, which is by far most of their parts business. Those who modify their cars are a much smaller crowd, so it is harder in that respect.

Since my Truck is stock, I have never received a wrong part from Toyota using my VIN.

As said above, Toyota gaskets and seals are fantastic quality and are really only matched or exceeded by purpose made, true high performance gaskets and seals (not found at your generic parts store).

Wear can take a toll on sealing surfaces over many years of use and it can be tricky to get any new seal to seal well if the sealing surface isn't in good condition. Pitting and wear grooves are the most common problems for seals that seal shafts.

Anyway, congratulations on getting your 4Runner almost completed! I bet it was a lot of work!

pplusent

Thank, it's been two years in the making.
As far as seals, the transmission was from a 92 and I don't have the VIN, But the seal fit properly and had the right amount of pressure on the sealing surface. I was lucky to find a tranny with very little were on it. There was no were groove on the contact area. Usually it is not that way and a repair sleeve is needed, but this one was good. I think the seal may have folded over when the T-Case was attached, or maybe it does not like the synthetic gear oil.
The front axel is a different story. I had the vin on that one and I don't think the 4 wheel drive had ever been engaged. The parts had literally no wear, everything measured out to factory spec, but the seal still has a tiny leak. I will just wipe the drop off every week it's just not worth a tear down of the unit. I think the problem is that this 4runner came with Murphy's laws included.
For now it is exceeding my expectations off-road, I have added lots of cosmetic extras like an abundance of Arizona pinstriping and reworked the bumpers in a few spots. All good since it is a 4x4.

Kolton5543

I'd have to agree, Toyota is the best seals to put in their vehicles. If they leaked right out the gate, something is messed up. Either a part is grooved, the seal is wrong, or it was installed incorrectly. Something many people miss is a lot of seals have a spring on the inside that keeps the rubber sealing surface tight to the component its sealing on. Sometimes these springs pop out when the seal is pounded in and goes unnoticed. I like to pack the grove it sits in with grease prior to installing the seal to ensure it doesn't pop out. Also if you've never seen a failed aftermarket seal, you must not have installed many seals. I've been working on cars for maybe only 8 years and professionally for less than 3 and seeing a failed new component is nothing out of the ordinary these days. If at all cost, I try to install OEM parts due to bad aftermarket. In the case of seals and gaskets, I prefer National, SKF and Fel-pro for aftermarket stuff. Even still, I get an occasional DOA OEM part. Doesn't matter what manufacture I'm working on

As for the Fluid loss, check the t-case fluid level. Just because there is a seal on it doesn't mean fluid cant cross over. If fluid managed to get out of the trans into the void then it has potential to get into the t-case. If its only in the void, it probably wont hurt anything but ideally, the problem should be fixed. If there is no fluid in there and your certain its going somewhere, you just gotta search harder. The stuff doesn't just mysteriously disappear. The clutch fluid can leak inside the cabin and sometimes takes a while before its easily visible. Also the rubber hose from the firewall to the to the transmission often times leaks on these trucks.

pplusent

I've been doing this a long time and have used many aftermarket seals and as long as you buy quality seals it's no problem, But lately everything aftermarket has been an issue. To much China made stuff out there and getting harder to find quality made stuff. Never an issue back in the day.