Hi,

I recently bought an old double cabin pick-up toyota hilux (1989, 4WD, manual). I am not familiar with them at all, as up until now I drove and worked on a toyota starlet.

This morning, I found that transmission(?) oil (clear oil) was leaking from the transmission box underneath the front seats (= called rear differential?). I don't know if this has been going on for some time or that it is something that started recently.

I do know that sometimes, when accelerating, noises where coming from underneath the car and I figured it might be some part of the drive shaft axle.

Anyway, the leakage seems to be coming from where the drive shaft axle goes into that transmission box. But I'm not sure. Also, I do not know what is causing this leakage...

Here's some images:





Any ideas as to what is the problem?

 

Thats the transfer case. You need the output seal replaced.

 

You might have lost alot of hypoid gear oil...so remove this big 15/16" plug and top it off.

 

Thanks for the very quick replies and helpful edited image, toyota4x4907 and ZUK.

Replacing the output seal... any suggestions on how that is done? (Useful links?)

@ZUK - topping it off until a bit of overflow occurs at the big 15/16" plug you pointed out, right?

(I hope I didn't drive in the car after the leakage started as I suppose it won't be a smart thing to drive it when the output seal is not yet replaced, even if the transfer case hypoid gear oil has been topped of?)

Also: is this a simple wear and tear thing (it is an old car) or might there be a more serious underlying problem?

Thanks again!

 

I found some nice online instructions here: https://www.yotatech.com/forums/f115...62/index2.html and here: http://www.4crawler.com/4x4/CheapTri...ionSeal/2.html

and started working on it. I have to buy a 30mm socket, though, before I can continue.

B.t.w. This morning I checked and saw that no further leaking has taken place. I had started the car to park it in a spot where I can work on it. No leaking. Throughout the day, I have not seen it dripping anymore, either.

I just checked the oil-level, and when unscrewing the 24mm fill plug, oil came running out! It seemed not to have leaked that much and there was sufficient oil still in the transfer case. Weird...

I think I'll continue and replace the seal anyway.

 

Transfer case might have built up pressure and was unable to vent. Try checking the vent system before you change the seal. Clean the oil off and check for leaks ,and keep watch for fresh oil after driving for a while.

 

Interesting! Too much pressure built up together with a non functioning vent system can lead to (temporary) releasing the pressure (and with that some oil) through the shaft seal? Does the release take place over a time span of a couple of hours?

Prior to the ( -temporary, it seems- ) leaking something did happen that might have caused pressure built up: I'd changed a flat tire for an old spare one someone had given me. However, the spare one did not fit right. The rim was actually right on the brake caliper. This I hadn't noticed. (Obviously, I'd never used the spare tire before, and -again- I only recently bought this car).

I drove the car for about 10-15 meters from one parking spot to another and then I noticed it. I took off the spare tire and saw that both the inside of the rim and the outside of the brake caliper were "groved" through the friction.

In other words, the left front wheel was actually sort of stuck/blocked, yet because of the strong engine of this pick-up, I could get it in motion without noticing it.

Would this cause pressure built up in the transfer case?

Where/how do I check the vent system?

Thanks.

 

I can't seemed to find the vent hose of the transfer case...
Unless it is the one pointed out in the image. (However, that hose goes all the way to the front of the car and then up to the dash board. It looks like the cable for the speedo-indicator..?).



Any ideas?

 

Vent would be on shifter base if present.

www.ncttora.com/FSM

:wabbit2:

 

how does that work?

(thanks for the link to your website, b.t.w.! Unfortunately, I did not find the FSM for a pick-up 4WD 5 speed manual from 1989. I think the '1984-1989 Toyota 4Runner FSM' might apply..?)

 

The vents are ON TOP of the transmission & transfer cases. That is the speedometer cable.

 

Ah, okay. And how do I clean those vents on top?