Oil Pan On My 08 1500

99silveradoz71 · June 23, 2008

Just finished a little oil change out in the garage. Now I've got boards on the 08 which I didn't have on my 99, and at 6'5 250(and change), I'm not a small guy. So it's hard to get under this truck even with the jackstands setup a couple notches and feel as comfortable as I did tinkering on my 99. Anyhow, tonight I rolled under and saw what appears to be a small amount of motor oil on this round thin metal disc/stamping that is on the oil pan. Also as you can hopefully see in the picture, near the front, I saw a semi-circular area where the edge of the pan is curved unlike the rest of it. Does this look normal, or did something happen? It was tough to take pictures, as the rounded metal tube is right in that area. Photos attached.

Rocco715 · June 23, 2008

Did you start it and check if it was leaking when the oil was under pressure?

99silveradoz71 · June 23, 2008

Just drained, changed the filter, and filled with Mobil 1. It fired right up and the oil pressure gauge went up to normal range once started. I'll have to check it out again in the morning. I just wasn't sure if anyone had seen that semi-circular edge on the front edge of their pan or not.

redcorvetteman3 · June 23, 2008

Check the Oil cooler block off plate. Mine did the same thing. Took it to the dealer 3 times and I am the one who found it on the lift. The block off plate is right above the oil filter.

Mike

VMax2007 · June 23, 2008

Bill,

Do a search. I have a thread about this and there are a few others too. I had this same problem, it is very common. You have an oil leak. Most likely your Crank Position Sensor and/or your Rear Main Seal. Look up near your starter, if there is oil on the bolt head(s) that holds your starter on, then it's your CPS O-ring. Oh, and FYI, the metal disc is an inspection hole for your flywheel, that is not the oil pan, it's the Bell Housing. You can pop that disc out and feel around inside there to check for oil too. if there is oil inside there, then it's most likely your rear main seal.

Here is a link to my thread, with pics: http://www.gm-trucks.com/forums/index.php?...=first+warranty

tobias · June 23, 2008

Bill,

Do a search. I have a thread about this and there are a few others too. I had this same problem, it is very common. You have an oil leak. Most likely your Crank Position Sensor and/or your Rear Main Seal. Look up near your starter, if there is oil on the bolt head(s) that holds your starter on, then it's your CPS O-ring. Oh, and FYI, the metal disc is an inspection hole for your flywheel, that is not the oil pan, it's the Bell Housing. You can pop that disc out and feel around inside there to check for oil too. if there is oil inside there, then it's most likely your rear main seal.

Here is a link to my thread, with pics: http://www.gm-trucks.com/forums/index.php?...=first+warranty

I too was a victim of the rear main seal.

99silveradoz71 · June 23, 2008

Jeff I recalled your threads about the seal and thought that was a possibility. Does that semi-circle notch seem like something happened or is that the way they're cast? I'll have to take her in tomorrow I suppose.

VMax2007 · June 23, 2008

Jeff I recalled your threads about the seal and thought that was a possibility. Does that semi-circle notch seem like something happened or is that the way they're cast? I'll have to take her in tomorrow I suppose.

It's part of the casting. Evidently they planned on them leaking so they provided a way for it to get out.

99silveradoz71 · June 23, 2008

Had me wondering about that. This truck is a little more difficult for me to scamper around under than the last one, but I'll just have to set the stands up a few notches higher next time. I just got off the phone and will drop the truck off in the am. They can have it all day to find that leak and do it right. I'll print the other thread to give them some ideas on where to look. Thanks again.

C & A s Dad · June 24, 2008

Bill, I have read some threads on this on the 900s. My 02 Yuk XL leaked and came out of the "weep hole" that you have pictured and showed up on the bolt heads on the driver's side. I thought it was the rear main but it ended up being the oil pan gasket.

The oil pan on our engines contains two holes that feed oil to the filter and back. These holes are just above the filter and are under pres and they contain silicone or nitril beads in the gasket around the holes. I had to diagnose mine myself but the dealer agreed, replaced the gasked and it has never leaked again.

This leak will fool many techs into thinking it is the rear main seal. The spinning flywheel will pull the oil from the area and make it seem like it is coming from the rear main. I have never read a post where this was the issue on a 900 but you never know.

99silveradoz71 · June 24, 2008

Hmm, well I printed my pics, and left them and the text from the other thread with the service advisor. She said she was going to attach them to the work order. The truck's been up there all day, and no phone call yet, so we'll see. I don't work until tomorrow night, so I told her if it ended up being the seal, that I knew it was involved and they could have the truck most of tomorrow too.

wlvrn1215 · June 24, 2008

I changed my oil the other day and it looked like there was some seepage between oil pan and bell housing...Think my rear main is starting to leak...what do you guys think??

crepitus · June 24, 2008

Jeff I recalled your threads about the seal and thought that was a possibility. Does that semi-circle notch seem like something happened or is that the way they're cast? I'll have to take her in tomorrow I suppose.

It's part of the casting. Evidently they planned on them leaking so they provided a way for it to get out.

thats the truth only mine was a trans fluid drain hole.

99silveradoz71 · July 8, 2008

Well they found a leak at the rear main seal, so Maxine was dropped off today for that repair. When it was there last week for them to check the dye and see if there was a leak, we discovered that she got hit while parked somewhere within the last few days. So they'll be doing body work to the right bedside. It never ends

Outbacker · July 8, 2008

It never rains, but it pours. That sucks, but thanks for the pictures and the info. I am going to put the front end of stands this weekend and check for leaks in this area.