'78 FJ40 Leak

[sepitome]

Hey folks,

Just picked up a '78 FJ40 and there is a small leak between the oil pan and the transmission housing. Any idea on what/where it could be ? It's a small leak and only seems to drip after I'm done driving and not if the truck sits for a few days. Thanks.

 

[ToyotaMatt]

Hey folks,

Just picked up a '78 FJ40 and there is a small leak between the oil pan and the transmission housing. Any idea on what/where it could be ? It's a small leak and only seems to drip after I'm done driving and not if the truck sits for a few days. Thanks.

View attachment 1758180

Thats More then a small leak , and u should Not drive the truck till u investigate it further


how much oil are u having to add every day or week ?

the reason it does not appear to leak while driving is its flying off your truck @30 or 40 or 50+ KPH or more

make stopping this leak and identifying it your priority

 

[Fast Eddy]

Or get the whole thing cleaned up so you can actually see how much is leaking.

Where it is sort of indicates a rear main seal, so it's a big deal (tm) to fix it. If it's a drip and a quart/year, you could leave it for a long time.

 

[EddieDLO]

brother Im on the same boat, I noticed a small stain the size of a golf ball on my drive way, anyways the pan didn't have a it have a rubber plug, just a hole. so ive been driving the heck out of it and haven't notice a drop in oil, should I pug the hole?

 

[65swb45]

1. Per @RAGINGMATT , keep a close eye on oil levels so you don’t hurt anything internally.

2. Clean everything up so you can identify fresh oil.
3. Gear oil has a different consistency than motor oil, so once you can put your fingers on fresh oil, you’ll be in a better position to identify which one it is.
4. It is very helpful to remove the inspection cover during diagnosis.

Best

Mark A

www.marksoffroad.net

 

[emac]

when I bought my FJ62 it had oil leaks like yours. I cleaned it all up and found about 1/2 dozen areas that were leaking!

 

[sepitome]

Thanks for the feedback. Just got an oil change so haven't added any oil and oil level seems fine. The truck sat for 5 years with the PO (or so I was told) so just finished changing all the fluids - front and rear diff, tranny and tc. Some of that wetness may be from the fluid changes. The tranny fluid was a nice, grey colour when I drained it. A bit also came out of the tranny fill plug when I pulled it. I guess I should clean it up first and then check. It's probably a case of the dried up gunk stopping the leak (as EMAC found). = )

BTW - Put this in the tranny / tc only GL-4 fluid I could find...
MotoMaster TDH Fluid, 5L | Canadian Tire

 

[dmaddox]

Rear main, more than likely. Follow above advice and you're golden.

 

[65swb45]

Overfilled trans=bad input seal on transfer case.

Welcome to the quirky world of Landcruiser ownership.

DO NOT BUY a bypass hose. You could cost yourself a much more expensive transfer overhaul by putting this off with a bandaid.

 

[Steamer]

You may want to check higher up also if you haven't already. A leak at the back end of the valve cover could run down to there. Swishing a rag on a stiff wire or rod between the rear of engine and firewall is one way to check and also to clean.

 

[sepitome]

You may want to check higher up also if you haven't already. A leak at the back end of the valve cover could run down to there. Swishing a rag on a stiff wire or rod between the rear of engine and firewall is one way to check and also to clean.

You may be on to something. I was out for a drive today and when I stopped there was a small pool of coolant under the truck. On the drive back home, things suddenly got a lot quieter from under the engine. It sounded a lot better, but I knew something was up. Pulled into the garage, hopped out and looked under the truck and saw a nice little green waterfall. Water pump bearing was gone ! I had 2 mechanical inspections done on it and the pre-trip inspection one said the water pump was failing and the safety one didn't mention anything. They may not have looked for it. Anyways, it may have been coolant being blown back past the engine bay to mix with all the grease on the underside. I drained all the coolant and nothing seems to be dripping (after a few hours in the garage). Now to find a water pump. Thoughts ? Need a fan clutch w/o oil cooler model. How do you tell if fan clutch is bad ? Thanks.

 

[Tancruiser]

Oh that’s not a leak that’s just Landcruiser seepage.

 

[GA Architect]

You may be on to something. I was out for a drive today and when I stopped there was a small pool of coolant under the truck. On the drive back home, things suddenly got a lot quieter from under the engine. It sounded a lot better, but I knew something was up. Pulled into the garage, hopped out and looked under the truck and saw a nice little green waterfall. Water pump bearing was gone ! I had 2 mechanical inspections done on it and the pre-trip inspection one said the water pump was failing and the safety one didn't mention anything. They may not have looked for it. Anyways, it may have been coolant being blown back past the engine bay to mix with all the grease on the underside. I drained all the coolant and nothing seems to be dripping (after a few hours in the garage). Now to find a water pump. Thoughts ? Need a fan clutch w/o oil cooler model. How do you tell if fan clutch is bad ? Thanks.

Cruiser Outfitters will get you covered on the water pump. > Click here <

 

[Heisenberg]

Hey folks,

Just picked up a '78 FJ40 and there is a small leak between the oil pan and the transmission housing. Any idea on what/where it could be ? It's a small leak and only seems to drip after I'm done driving and not if the truck sits for a few days. Thanks.

View attachment 1758180

 

[Heisenberg]

Hey not sure if you’re still on here but I have a leak in the pan you labeled with the rubber plug. I assume it’s something transmission related. I’m not mechanical but get by. What is that part?? I have a hole instead of a rubber plug. Oil/fluid sitting around bolts -

 

[charliemeyer007]

Spray on some degreaser at the wand car car wash, let it soak for a while then power wash it off. That way you will be able to better identify where it leaking. Check the fluid level in both the tranny and transfer. If the seal between the 2 is leaking fluid from the transfer will pump up to the tranny.