Replace Pan and Main Gasket - On Truck?

[LBJ]

I have a pretty good engine oil leak right above the main cross member. Looks like the front main seal right under the timing chain cover. Can you get to and remove the oil pan while the engine is in the truck? I bought a one piece neoprene type gasket, but would like to know if it is doable before I set out on the replacement. Thanks, LBJ

[James McClure]

LBJ: 2 wheel drive or 4? 2 wheel drive can be done in the truck but it ain't easy. 4 wheel drive is a piece of cake. If you replace the damper seal pay close attention to the condition of the hub on the damper. Over time and high mileage they get grooved and new seals start leaking almost right away. NAPA sells a "wear ring" you hammer on to the hub before you install it and it works great. jim

[LBJ]

James McClure,

It's 2 wheel. The truck has around 80K miles, I suppose. Now, are you talking about just pulling the pan? Or more?

[old Rusty C10]

if memory serves me correct you have to unbolt the motor mounts and jack up the motor and stick 2X4s in there and let the motor down onto those to be able to drop the oil pan to replace the seals/ oilpan gasket.. I believe its tight too to get past the oil pickup but it is doable
its been years since i did this job on a 2wd truck so thats my best recollection

[Slonaker]

I did it twice on my '86 C10. I didn't have to jack up the engine or anything. There was plenty of room to get it in and out.

Slonaker

[N2TRUX]

You "should" be able to get the pan off without jacking the motor. If you do need to raise the motor a bit, turn a 2x4 on it's side and put it under the damper to get a bit more room. Don't forget to watch the dizzy cap that it doesn't get smashed against the firewall.

[LBJ]

Slonaker, Let me ask you something. Why did you do it twice? <grin>

[87 STEPPER]

Like the other have said it can be done in the truck but the 1 piece seal won't work on your '77 block unless you have installed a newer block that uses the one piece seal.

[swb85]

Originally Posted by 87 STEPPER

Like the other have said it can be done in the truck but the 1 piece seal won't work on your '77 block unless you have installed a newer block that uses the one piece seal.

He's talking about the oil pan gasket, not the rear main.

There's plenty of room to do this, I've done it three times on my truck on two different motors. It's a piece of cake if you're comfy on your back.

[LBJ]

So, now it seems I can't use the one piece pan gasket on my old block. Correct? The seal that's the worst is the front, but I suspect the rear is leaking too. Go the old way with individual seals for the front and rear mains, and separate pan gaskets?

[James McClure]

LBJ: Morning. This is just my opinion so take it for what it's worth. If it were my truck and I had multiple leaks, oil or coolant I would cut to the chase and just pull it out and reseal the whole thing and be done with it. Ya, it's more work in the short haul but in the long run you'll be better off. If it's high mileage and the age is getting up there check the frost plugs too. jim

[spudz]

If you got the time...ITS REALLY nice pulling the motor and putting it on a stand and resealing it.. Then you could clean and paint everything.

[swb85]

Originally Posted by LBJ

So, now it seems I can't use the one piece pan gasket on my old block. Correct? The seal that's the worst is the front, but I suspect the rear is leaking too. Go the old way with individual seals for the front and rear mains, and separate pan gaskets?

Yes you can use the one piece pan gasket on an old block. What 87 stepper was referring to was the rear main seal around the crankshaft which went to a one-piece design in the late 80's.

With the pan gasket, the front seal that goes between the timing cover and oil pan came in two different thicknesses. Make sure you get the right one. Yours should be the thick seal if I remember correctly. You'll know immediately when putting it on if it's right or not.

[Slonaker]

Originally Posted by LBJ

Slonaker, Let me ask you something. Why did you do it twice? <grin>

That's a long story....

My truck had what I think was a 305 crate motor in it rather than the original 305. The block had the bulge for the dipstick on both sides of the block and pan, but was only drilled for the dipstick on the passenger side. I installed a Fel-Pro stock '86 pan gasket, and found out that it doesn't seal the bulge on the driver's side because the bulge isn't supposed to be there. I lost a quart or two of oil just in a few miles of driving.

None of the local parts stores could find a part number for an oil pan gasket with the bulge on both sides that fits a block with a one piece rear main seal ('86 was the first year for the 1 piece rear main seal). No one on here knew what I needed, either. It was easy to find one for the two piece rear main seal engines because all of the crate engines (like the one I have now) are drilled for a dipstick on both sides, but no luck with mine.

I ended up having to go to the dealer, and they were able to use the part number on the pan to get a part number for the pan gasket. There was only one gasket available in San Antonio from one dealer, and it was almost $80. Ouch!

A few days later, the guy at my local O'Reilly said "Hey, I finally found the Fel-Pro number you need." It was a special order item, but only like $12 or so.

Slonaker

[LBJ]

I may delay this till warmer weather. It can change from 65 degres F like today, to 20 degrees in just a short time. I have to work out in the open driveway, so no protection from the cold wind or rain. I may end up pulling the engine out next Spring and doing some sealing up. The engine runs fine, but I hate to have leaks. Just bugs me. I did give a look at the clearances. Moving the trans cooler lines and fuel line out of the way and using an air ratchet, it may be possible to do it! It is difinitely leaking either from the pan or crankshaft seal on the timing chain cover. They are right on top of one another, so hard to tell exactly. I suppose that timing chain cover sould be done in place too, but would have to take off the accessories to get to it. Be worth it to get those leaks stopped. That might be a good time to change out the A/C seals since things would be out of the way.

By the way, I bought the one piece gasket that has the holes on both sides for the dip stick. May have to take it back to Auto Zone.