Replace oil pan seal

[deejay1272]

It appears that I have a small oil leak near the front of my motor. I can't confirm, but it appears to be coming from the oil pan near the front of the vehicle. I was planning on simply taking the oil pan off and replacing the gasket seal next time I change the oil to attempt to address this issue.

First - Should I consider investigating some other source of the leak (is there a more common problem that I'm missing )?

Second - Is there anything difficult or potentially challenging about removing the oil pan

Third - The FSM mentions that I should use a "non-residue" solvent to clean the contacting surfaces of the oil pan. Any product recommendations?

Fourth - I'm wondering if I should think about replacing the oil pump while I'm in there. Do these things fail often?

Thanks!

[Petros]

oil pumps are pretty durable, replacements are costly. If the pump sucked in a lot of grit it will be gone, but mine has 280k miles on it and still pumps plenty of pressure. test with a oil pressure gauge (they do not cost much) to see the condition of the pump, easy way to check compared to replacing a pump.

Most common cause of oil leak is front main seal, or cam seal. Very rare pan gasket suddenly starts leaking, more likely it is running down the front of the engine and running along pan lip. while you are replacing the front seal you might as well replace the timing belt (cheap), possibly upper seal and tensioner pulley (if bearing is not smooth turning). Replacing the water pump is easy access and no need to do it with the timing belt since all bolt are accessible. IF you do replace the water pump I highly recommend a new one, not rebuilt (most are junk), new does not even cost much more. I think NAPA has a lifetime water pump.

Removing the oil pan is a major job, both the cross member and the front diff is in the way. It can be done, it helps to unbolt and lower the cross member a few inches (you have to support the engine from above). But if the leak is not bad I would wait until you have a reason to remove the trans (for a new clutch and rear main seal change) or remove the engine for a rebuild or modification. Likely it is not the oil pan. It might be possible to back off the pan bolts around the leaking area (once you have determined it is the pan) and carefully pry it apart and put in Form-A-Gasket sealer at the leak, and put it back together. Not ideal but about 4 hours less work.

good luck.

[splatterdog]

I would second the cam and/or crank seal. Even the front of the valve cover could simulate a pan leak. If it was the pan, I would pull the engine. In car pan pulling/repairs suck on most vehicles. There is no "simply pull the pan" on a T4. Half assing it by dropping the pan to goop it is going to be time wasted too. 4 hours would be better spent on engine R&R. Plastigage the crank bearings at the same time..

Stay away from most "lifetime warranty" parts. That phrase was developed by marketing teams looking to set the hook in YOU. The best warranty is one you don't need. OE or anything else before Chinese junk for me. Most Toyota/quality stuff, if it makes it for that one year of warranty, will likely last a decade or two.

As far as replacing the oil pump. I wouldn't make any moves without knowing exact oil pressures and crankshaft bearing clearances.

ANY sealing surfaces should be nearly sterile before assembly.

It could be worse. You could have a modern car.

[dlb]

It could be worse. You could have a modern car.

big like on this comment.