Oil Leak

[John Boothby]

I just developed what appears to be a major oil leak. I had only added 1 quart of oil since the last oil change, which I thought was about normal from all that I have read. Anyway, I was parked on about a 3 or 4 degree nose up incline for about 30 min (Barber shop). When I came back to the car I noticed a puddle of oil under the car in the proximity of the rear of the engine. Probably 1/4 quart! I checked the oil level and it was down about 1 & 1/2 quarts. I believe it is a rear seal. Anyway, has anyone had to replace a rear seal in an LT5? Are they hard to come by? Any idea of cost including labor through a dealer?

Note: I have not noticed any leaks up to this point. It appears to have come on suddenly. Any thoughts on this?

[Jeffvette]

Seal is available, you can do it in your garage. The trans has to be removed and that's it.

[John Boothby]

I could do it in my garage, except for two things. One is that I have no way of getting the car off the ground far enough to remove the tanny. Number two is that the development where I live, I am prohibited from working on my car (UnAmerican, in my opinion!). Yes I know, this is my choice!

Anyhow, I have an appointment next Wednesday at one of the local Chevy dealers. I just thought that someone may have an idea as to what I am looking at in the way of cost. Great way to bring in the new year!

[Jeffvette]

Figure roughly 5 hours R&R for the tranny, and then maybe an hour for the seal, and then parts. Have them change out the tranny fluid to the BMW fluid while they are in there.

[John Boothby]

By "BMW" fluid, are you talking BMW as in "Bavarian Motor Works"?

I just talked to the dealer and he gave me an "off the top of his head" price of around $1,200. He also said it might be an intake seal. ??

[bobbyhi]

Can't the dealer give you an estimate for repairs? Here in Minnesota you can request an estimate that can not go over by 10%. Good luck on the repairs...

[Jeffvette]

By "BMW" fluid, are you talking BMW as in "Bavarian Motor Works"?

I just talked to the dealer and he gave me an "off the top of his head" price of around $1,200. He also said it might be an intake seal. ??

Yes BMW M5 motor oil. It's a substitute for ZF6 transmission oil.

Intake seal is L98 and LT1 territory. I would not recomend you go with that dealership.

6 hours of labor at 70 per is 420, and the seal at the high end of dealerships might be 45 bucks. 1,200 is outrageous. If you had a place to work on it, I'd be willing to fly down and do it.

[Jeffvette]

BMW part number for the oil 07510009420

Need 3 litres of it. You'll use 2.25 of them.

[cuisinartvette]

Jeff, have a PN o the rear main? Looks like mines leakin' too. I assume its a 1 piece type that pops out and new one just presses in?

[John Boothby]

Thanks for all the info and offers of help guys!

The Chevy dealer has always been good to me. When I asked "how much" he just gave me a quick figure which is high. He also stated that it might be something else.

I do not know for sure what it is, as I cannot get under the car to see it. I have not actually seen it leaking, but I started it up this morning and backed it out on my driveway (which is on an incline) for a few minutes and checked the mat that I keep under the car. The mat was soaked. When I drove the car back into the garage the driveway had a couple of oil spots, each the size of a quarter, in just that short period of time. I have added 2 quarts of oil since yesterday morning. I have only put about 25-30 miles on it since then.

I am not driving the car until I find out where this leak is. It came on so fast and I do not want to hurt this motor! I am having the car taken to the dealer Monday morning via flat bed truck. I have already asked the dealer if I can get under the car to see for myself what it is, and he said "no problem".

Jeff, thanks much for your offer. I hope you have a very happy and safe new year!

[Jeffvette]

Jeff, have a PN o the rear main? Looks like mines leakin' too. I assume its a 1 piece type that pops out and new one just presses in?

Seal 10088158
Gasket 10168681

I would replace both while you are in there. List on both items is around 28 each.

[Jeffvette]

Thanks for all the info and offers of help guys!

The Chevy dealer has always been good to me. When I asked "how much" he just gave me a quick figure which is high. He also stated that it might be something else.

I do not know for sure what it is, as I cannot get under the car to see it. I have not actually seen it leaking, but I started it up this morning and backed it out on my driveway (which is on an incline) for a few minutes and checked the mat that I keep under the car. The mat was soaked. When I drove the car back into the garage the driveway had a couple of oil spots, each the size of a quarter, in just that short period of time. I have added 2 quarts of oil since yesterday morning. I have only put about 25-30 miles on it since then.

I am not driving the car until I find out where this leak is. It came on so fast and I do not want to hurt this motor! I am having the car taken to the dealer Monday morning via flat bed truck. I have already asked the dealer if I can get under the car to see for myself what it is, and he said "no problem".

Jeff, thanks much for your offer. I hope you have a very happy and safe new year!

A few things to check.

Do check the rear main seal. You will probably also have a little seepage into the bellhousing as well and some gunk around the base of that.

Check all your oil pan bolts to make sure they are tight.

Check the top end of the block to see if you are getting any leakage from the PCV system. Oil is only up to the injector housings, so you might be getting leaks/pooling and sitting on a incline cause it to run down the back of the block. But with the amount you described, I doubt this is the issue.

How much oil was added in the last oil change, when was it done and did you do it?

Hope you have a good New Years as well.

[John Boothby]

The last oil change was done by the dealer on Sept 26. He added 10 quarts Mobile 1 5W30. The filter was replaced. I also had the tranny and diff changed as well as engine coolant. The car only has about 1,500 miles since this last oil change. I originally had an appointment for an oil/filter/lube service on Wednesday next week.

[Jeffvette]

The last oil change was done by the dealer on Sept 26. He added 10 quarts Mobile 1 5W30. The filter was replaced. I also had the tranny and diff changed as well as engine coolant. The car only has about 1,500 miles since this last oil change. I originally had an appointment for an oil/filter/lube service on Wednesday next week.

10 qts is to much oil. Especially if he didn't let it drain for a while. Dealer should owe you for this, IMHO. But proving it is another issue.

[John Boothby]

Jeff, you are correct. The manual states 8.6 quarts with filter change. I checked the last oil change receipt in June, 05 and it shows 7 quarts were added. I did not question the higher amount this time because I thought that I had read the LT5 took more (12 quarts comes to mind). Maybe bone dry! I just checked the manual for an oil change and the above 8.6 quart figure is referenced. I check the oil level after each oil change and do not recall it being over the full mark.

I am taking the receipts back to the dealer and question him on this. They had replaced the A/C compressor clutch for the previous owner with an incorrect one that continually shredded the belt. I questioned him on this, and they replaced it with the correct one, no charge. I have learned that I must continually remind them that this is an LT5. I am surprised, because this dealer, and his supposedly ZR1 trained mechanic, come highly recommended by other ZR1 guys in this area that I have talked to.

The oil pressure usually stays in the lower to mid range on the gauge, however, it does get up to the high end on initial start up and hard acceleration. I don't think I have seen it peg, though.

By the way, enlighten me to "IMHO".

[Z Factor]

I have learned that I must continually remind them that this is an LT5. I am surprised, because this dealer, and his supposedly ZR1 trained mechanic, come highly recommended by other ZR1 guys in this area that I have talked to.



By the way, enlighten me to "IMHO".

IMHO is an acronym for In My Humble Opinion.

As to the mechanic being "ZR-1 trained", you should ask to see documentation that he completed training, as anyone can say they are trained/certified.

:cheers:

[John Boothby]

Yes, I know. I have talked to both the dealer and mechanic and felt comfortable with them. I have not seen certificates. I guess that I am too trusting. However, other ZR1 owner's I know in the area, have recommended them including the previous owner.

I only wish that I had a garage with a lift where I could work on it my own self! Damn cc&r's!!

Thanks for the interpretation of "IMHO". First time I have seen that.

Happy New Year!

[John Boothby]

Well, the news is that the leak is from a cracked oil pan. Naturally, the dealer cannot find one, so we are looking at welding it. Has anyone had any experience with welding these pans? They are aluminum, and can be welded, correct?

Just for grins, does anyone have, or know of an oil pan for an early LT5 available for purchase? Cost?

I had run over an exceptionally high speed bump on Dec 9 and apparently cracked the oil pan. I remember the bump. I crawled over it, but it had steep approach and departure angles and when I came down it bottomed out. I did not realize that it cracked the pan. Fortunately, it only got down about 2 quarts of oil before I noticed the leak and added oil.

[Jeffvette]

Damn John, that sucks. A few pop up on ebay every now and then. You should be able to weld it no issues. Just find a guy who is very experienced in working with alum.

[John Boothby]

The pan is going out to a machine shop for welding. I am going to have them Dye-glow it when it is finished to check for any other cracks. At least, this is what we used to do with non-ferrous metals.

[1990 quasar blue]

I think that welding it should be fine as well. However, I found this, and thought that it may help. http://www.lt5-parts.com/library/catalog/default.asp?title=&menu_id=&cat_id=4787&cat_name=Misc%2E+Engine+Parts&cat_list=&page_num=2

:cheers:

[John Boothby]

Thanks for the info. I emailed them regarding their oil pan. I will find out what the estimate is for repairing the old pan, but $350 does'nt sound too bad for a new one.

[John Boothby]

Well, I ordered a complete new oil pan assembly from DRM, including the gasket. The dealer had already had the old pan welded at a cost of $84.50. So it looks like I will have a spare oil pan!!