Oil pan seal

Started out with the oil pan having a progressive leak under the front cover, amongst other leaks. I pulled the engine to re seal the pan. I did use the ford gray silicone. After torquing the pan down I kept the garage at 70° for the first 8 hours. I did see the silicone ooze out around all sides of the pan. After getting everything together I drove it around town for about 30 miles with no sign of a leak. I hit the road heading home and about 150 miles later I stop and see a large amount of oil underneath. From Chugwater, WY, back to Denver, I lost about 2 gallons of oil. My question is, how did it blow out that fast? The engine has 195xxx miles. I'm questioning if I have low compression on a cylinder or not. I have not done a compression test. When I had the pan off, I did not see any lines or scores on the cylinder walls, with the cross hatch still visible. The whole trip it was running great, with a little bit higher oil pressure than it normally has. Thanks in advance.


Sent from my iPhone using Tapatalk

How long from the time you applied to the silicone until you started the truck? 8 hours? Might not have been long enough to dry completely

Is your CCV blocked or clogged?

Does the truck start easy? What's the oil gauge on the dash showing? Sometimes guys crack the blocks with pan reseal jobs. Excessive silicone getting onto the bolts or into the bolt holes can hydrafracture the block casting and split the oil rail open. Not saying that's your issues but 2 gallons in that amount of time driving is massive

Well since I live 200 miles away from the place I was working on it, I ran short on time so it had 2 weeks to setup. However, all but 24 hours of that was probably about 50°. Like I said, the first 8 was about 70° and over night was about 60- 65°.

The CCV is clear. It is re routed under the cab with no more blowby coming out of the tube that what comes out of the oil fill.

Yes, it does start easy. Oil pressure was a little higher than normal, around the upper 3/4 of the gauge. The silicone bead was about 3/16" wide, I circled the bolt holes and left room so it wouldn't fill the holes when it smashed down.

I will be going back next week to do a compression test and go from there.


Sent from my iPhone using Tapatalk

Did you reseal the dipstick nut too?

Is the oil coming from a specific side or from everywhere?

Could be your front cover leaking too.

Yes, new I ring on the dip stick nut with blue locktite to prevent it from backing off. Also used standard grey silicone where the tube goes into the plug.

It looks like it's coming from both sides of the pan. However, I can't tell exactly where due to airflow blowing it around. The front cover is dry all the way around. No oil in the valley, just on the bottom end.


Sent from my iPhone using Tapatalk

Did you take a straight edge to the oil pan before resealing?

Did you lay a heavier bead around the timing cover and corners of where the pan/timing cover/block meet?

And did you use a new oil pan? If you re-used your old pan, the pan rails could be possibly warped from prying it off.

Billy T.
[email protected]

Pan was straight. Took a putty knife all the way around so it just lifted off. Yes I did lay a heavier bead on the corners.


Sent from my iPhone using Tapatalk

I had a few oil pan bolts come loose fairly fast after changing mine. Had a similar oil leak. Run them again make sure none loosened.

That was the first thing I checked, and they are all good. Now even if a few came loose, would it still seal up properly?


Sent from my iPhone using Tapatalk

I should say would it still seal after tightening the loose ones?


Sent from my iPhone using Tapatalk

Mine did. Have not had even a hint of oil on the pan.

I was thinking... I just did another oil pan job on my buddy's '99. after getting it back in the truck and running it, we had a bad leak like yours. Turns out he (I was not present) bumped the pan on the crossmember when putting it back in. Enough so that it broke the silicone seal. We pulled the motor again, re-sealed it, put it back in without hitting anything and voila, no leak.

Did you bump it into anything by chance?

Also, FWIW, my silicone was definitely not dry after 8 hours so I still think it's possible that might be your issue.

As far as I know I did not bump it on anything. Even sitting around 60° for 24 hours, wouldn't that be enough time for it to dry? The parts that oozed out we're definitely dry.


Sent from my iPhone using Tapatalk

CTFFEMT said:

Mine did. Have not had even a hint of oil on the pan.

I was thinking... I just did another oil pan job on my buddy's '99. after getting it back in the truck and running it, we had a bad leak like yours. Turns out he (I was not present) bumped the pan on the crossmember when putting it back in. Enough so that it broke the silicone seal. We pulled the motor again, re-sealed it, put it back in without hitting anything and voila, no leak.

Did you bump it into anything by chance?

Also, FWIW, my silicone was definitely not dry after 8 hours so I still think it's possible that might be your issue.

Click to expand...

If there was nothing before, these two suggestions are top of my list.
Also they are easy to fix if thats the case but the block was cold the inside of the pan was cold so I'd venture that could be the case.

Refill, clean off all the oil you can. Start it and let it idle for a while, it make take some time but you might be able to spot your leak.

Start simple if you can. Also, compression #'s are good to have IMHO.

It's possible that the silicone didn't setup properly, but I'm still going to do a compression test and go from there.


Sent from my iPhone using Tapatalk

Does anyone know what the optimum temp the block and pan needs to be for the silicone to adhere properly?


Sent from my iPhone using Tapatalk

1- 380 psi
2- 340 psi
3- 350 psi
4- 340 psi
5- 340 psi
6- 340 psi
7- 340 psi
8- 380 psi
Maybe I didn't use enough silicone...


Sent from my iPhone using Tapatalk

http://www.permatex.com/products/our-brands/the-right-stuff

The only sealant to use, standard rtv doesn't seem to be effective in helping to seal gaskets. I used this on my trans pan without a gasket, with no leaks period (mag-hytec pan that the oring seal wouldn't seal).