Oil Pan Gasket Change

[John Coulter]

Does anyone have step by step instructions for changing out the oil pan gasket? I have an 09 Tahoe 5.3 2 wheel drive. Also, do you recommend changing any other parts while I'm there? Thanks.

 

[kbuskill]

It's pretty straight forward if you are mechanically inclined.

You didn't say how many miles are on your truck but assuming it's over 100k I would install a new O-ring on the oil pickup tube at the very least and possibly even install a new oil pump while your that close and if you do that you may as well install a new timing chain set.

Get the truck up on ramps (or a lift).
Drop the crossmember under the oil pan.

If you need new engine mounts now is a great time to replace those as well. If you do get the mounts for the Hummer H3.

If you do replace the engine mounts then get a cherry picker and lift the engine up to remove the mounts and the pan. Be very careful with the intake manifold to firewall clearance. I had my intake off when I did this so I don't know how close it will get.

Alternatively if you don't lift the engine then you will have to drop the steering rack to get the oil pan out.

If you decide to do the oil pump and timing chain then you will need to purchase a new crank/harmonic balancer bolt as they are a TTY bolt and stretch. If you go this route then I would also suggest buying a tool like this...
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/231834672301

To hold the flywheel still while breaking loose and tightening the crank bolt. This tool bolts up in place of your starter.

I also purchased a Massive crank bolt...
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/232527389939

Because I hate TTY bolts.

The pump I installed was a Mellings HV/HP oil pump... it comes with the HP spring installed in the pump but also comes with the standard pressure spring if you prefer.

The AFM engines come from the factory with a HV pump standard.

I ended up with what the ECM considers "too much" pressure so it would always set the CEL for oil pressure out of range. I would have 70-75psi cold oil pressure and 65-70psi hot oil pressure. I refused to go back in just to change a spring so I used a resistor to trick the ECM into seeing "normal" pressure.

If I were you I would just install a HV pump and save yourself the headache.

I also installed a new oil pressure relief valve in the oil pan while I had it off.

Hope this helps.

 

[David Smith]

I would also recommend replacing the oil pickup tube u-ring as well. It really is not difficult.

Drop crossmember
Unbolt steering rack
Drain oil
Remove all bolts holding pan on and remove pan(there are quite a few, so triple check before yanking on it)
You will have to work around the steering rack, but since it is unbolted, you will have enough play to get the pan out

***This is where you would do the pickup tube o-ring
*Remove the nuts and bolts that hold on pickup tube
*Remove bolt that holds tube to pump
*Pull tube out (clean if while it is out)
*Install new, lubricated o-ring on tube
*Carefully install tube back into pump
*Reinstall all nuts and bolts (torquing them properly)

Clean oil pan out and remove old filter
If it is the factory gasket, there will be 2 rivets that you will need to get out of them pan (I drilled mine out)
When I did mine, I bought some gasket maker to put on the bottom of the motor. Only where the timing cover mates the the block and where the bell housing mates to the block.
Reinstall pan and torque down all botls
Fill new oil filter with oil and lubricate o-ring on filter then install
Fill her up with oil
Celebrate.

I may be missing some small stuff like unplugging sensors and what not, but that will be obvious once you get under the truck and see what you have got.

 

[Mr T]

It's pretty straight forward if you are mechanically inclined.

You didn't say how many miles are on your truck but assuming it's over 100k I would install a new O-ring on the oil pickup tube at the very least and possibly even install a new oil pump while your that close and if you do that you may as well install a new timing chain set.

Get the truck up on ramps (or a lift).
Drop the crossmember under the oil pan.

If you need new engine mounts now is a great time to replace those as well. If you do get the mounts for the Hummer H3.

If you do replace the engine mounts then get a cherry picker and lift the engine up to remove the mounts and the pan. Be very careful with the intake manifold to firewall clearance. I had my intake off when I did this so I don't know how close it will get.

Alternatively if you don't lift the engine then you will have to drop the steering rack to get the oil pan out.

If you decide to do the oil pump and timing chain then you will need to purchase a new crank/harmonic balancer bolt as they are a TTY bolt and stretch. If you go this route then I would also suggest buying a tool like this...
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/231834672301
View attachment 204177
To hold the flywheel still while breaking loose and tightening the crank bolt. This tool bolts up in place of your starter.

I also purchased a Massive crank bolt...
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/232527389939
View attachment 204178
Because I hate TTY bolts.

The pump I installed was a Mellings HV/HP oil pump... it comes with the HP spring installed in the pump but also comes with the standard pressure spring if you prefer.

The AFM engines come from the factory with a HV pump standard.

I ended up with what the ECM considers "too much" pressure so it would always set the CEL for oil pressure out of range. I would have 70-75psi cold oil pressure and 65-70psi hot oil pressure. I refused to go back in just to change a spring so I used a resistor to trick the ECM into seeing "normal" pressure.

If I were you I would just install a HV pump and save yourself the headache.

I also installed a new oil pressure relief valve in the oil pan while I had it off.

Hope this helps.

Can one fully replace the oil pump if only the oil pan is removed or do you have to obtain full access to the back of the block (i.e. move the tranny)? I'm doing an oil pan gasket job on my 6.2L soon and wouldn't mind the entire pump at the same time. I'm mechanically inclined but never removed the pan on this chevy, so I don't know how much access you have to it with only the pan dropped. Thx.

 

[kbuskill]

Can one fully replace the oil pump if only the oil pan is removed or do you have to obtain full access to the back of the block (i.e. move the tranny)? I'm doing an oil pan gasket job on my 6.2L soon and wouldn't mind the entire pump at the same time. I'm mechanically inclined but never removed the pan on this chevy, so I don't know how much access you have to it with only the pan dropped. Thx.

The transmission can certainly stay in place.

The timing cover will have to be removed though as the oil pump on these LS engines is driven off the front of the crankshaft.

You drop the oil pan and pull the timing cover and timing chain and the oil pump is right there on the crank.

I would suggest a new timing chain and tensioner while your in there.