Transmission Oil Leak

GTO-909

GTO-909

Member
Have not been able to drive my Deli as of late. Transmission leak. Slow, has gotten a bit worse. Spots on driveway to bigger spots. It isnt oil as the color is not black... just oily. 100% sure it is trans fluid. I am hoping it just needs a gasket. Just ordered Napa # 17805. Driving a 1990 L300 Automatic Diesel. Any guidance?
 
The drivetrain can leak from many places, randomly changing gaskets can just create more leaks. Best to figure out where the oil is coming from first. I'd thoroughly clean and degrease the drivetrain, then watch for oil coming back. Take a photo of the oil drip on the transmission.

Figuring out which fluid it is is fairly easy- put something white under the van and wait. Transmission fluid is red, engine oil black, transfer case is clear/yellow, coolant green (or it should be- you must use antifreeze in this engine, and green is easier to spot than orange). Rear differential oil is the same colour as transfer case oil, but much further back ;-). Diesel is clear/yellow, but very thin.

That said, the most common culprits on each component are the drain and fill plugs (no-one uses a new crush washer like they're supposed to), the transfer case side cover (the square steel one, it gets bashed on rocks and starts to leak), and the automatic transmission oil pan (the factory gasket works when it's brand new, but overtighten the bolts just once and it'll leak forever after. Throw the gasket out and seal it with high strength grey silicone. Same with the transfer case side cover).
 
Just trying to get back in the swing on the leak. Have not drove the Deli in 2 months. I’m bummed. @Growlerbearnz , thank you for the detailed and informative reply. I’ll start with the cleaning the bottom of my Deli for observation and switching out the oil drain plug with a new one along with a crush washer.

Any info on getting the right plug without having to pull out my current one? I gave a transmission oil change back in November and couldnt find the correct replacement... thus former plug and wash is still in use.
 
It looks like Im leaking out of the transfer case where the drive shaft goes in. Hadn’t done a thorough cleaning and assessment yet but I’m dealing with something similar somewhere. Good luck tracking it down.
 
Nenw said:
It looks like Im leaking out of the transfer case where the drive shaft goes in. Hadn’t done a thorough cleaning and assessment yet but I’m dealing with something similar somewhere. Good luck tracking it down.
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Front or rear driveshaft? Either one could be the driveshaft seal (an easy replacement) but on a manual gearbox'd Delica the rear driveshaft itself has a blanking plug behind the universal joint. That plug stops oil from leaking out past the sliding splines, but it sometimes comes loose and leaks. Can be fixed by cleaning and degreasing the area thoroughly, and sealing with grey silicone.
 
@Growlerbearnz

Leak resolved for now. Seems to have solved on it's own. I noticed my transmission levels were a bit high and ended up draining it to a more optimal level. Thereafter, leaking seems to have resolved on it's own. Prior to the leak ever becoming a concern I lived in NorCal and relocated to SoCal. Perhaps the temperature difference had an influence on the tranny oil level. In NorCal I would check it often and keep it to spec level... checking the oil level down here, the level was higher than what I had pour into it when I lived in NorCal. No oil leaks since the change in tranny oil level. Thanks for all your expertise! My Deli now has a start problem... I started a thread with a request for help.

In the meantime... I want to be more of an active member. I went AWAL for a bit as life's callings kept me from being more into my Deli. Got married recently. xD
 
Growlerbearnz said:
Front or rear driveshaft? Either one could be the driveshaft seal (an easy replacement) but on a manual gearbox'd Delica the rear driveshaft itself has a blanking plug behind the universal joint. That plug stops oil from leaking out past the sliding splines, but it sometimes comes loose and leaks. Can be fixed by cleaning and degreasing the area thoroughly, and sealing with grey silicone.
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I need to replace the rear driveshaft oil seal (comes out of the transfer case to the rear propeller/drive shaft). It has a seeping leak, no drips yet. Would you have the correct part number I can search for? Megazip narrowed me down to a couple part numbers, but I thought I'd check with the great @Growlerbearnz before just order more random parts that may not fit. Any help on instructions for changing these? or is it straight forward? Also, part numbers for u-joints would be great too! Thanks!!!
 
Transfer case front propshaft seal MD712012
Rear seal (auto) MD727653
Rear seal (manual) MD712012

Front propshaft U-joints MR196837
Rear propshaft U-joints MR196838
 
Growlerbearnz said:
Transfer case front propshaft seal MD712012
Rear seal (auto) MD727653
Rear seal (manual) MD712012

Front propshaft U-joints MR196837
Rear propshaft U-joints MR196838
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Thank you so much! You’re on it!!!!
Just to clarify by “rear seal”, your meaning the seal on the transfer case for the rear propshaft correct?
 
Growlerbearnz said:
Transfer case front propshaft seal MD712012
Rear seal (auto) MD727653
Rear seal (manual) MD712012

Front propshaft U-joints MR196837
Rear propshaft U-joints MR196838
Click to expand...
Hi Grant
I have 3 different numbers now for the rear transfer seal for my Van. VIN P24W-0201278. 92 JDM manual.
Mega Zip says MD727653
Epic data says MD731708
and you say above MD712012.
Are you able to shed some light or do I need to pull the shaft and measure before ordering, I don't fancy waiting 2 months for the wrong seal to arrive.
I checked the 2 sites above before searching here to clear things up and now I am really confused?
Thanks in advance for any wisdom.
Aaron
 
@aarongreenie are you auto or manual. There are variations in the t-case. And worse comes to worse order both. They are like $8.

Also, you say you are a 92’ but do you know your manufacture date?
 
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@Growlerbearnz that part is for the front output seal. Sounds like he is needing the rear. I totally overlooked the chassis code yesterday. I am seeing MD731708

ACE5E4B9-A76F-4748-B2B9-46657CC4838A.jpeg
 
Nenw said:
@Growlerbearnz that part is for the front output seal. Sounds like he is needing the rear. I totally overlooked the chassis code yesterday. I am seeing MD731708

View attachment 14538
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I will take your advice and order all 3. At least the front seal is definitely MD712012 so if I have that left over it is for my van. Otherwise I have to pull the shaft off just to measure it. Thanks for your help and @Growlerbearnz for checking up.
 
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