99 chevy blazer, rebuilt engine, oil leaking...what could it be?

There's no real way to tell with out looking at it. Sounds like you need a better place to get your work done to me though.

If you had to take it back once already, and so far it has not been repaired correctly, they maybe trying to patch up the leak rather than repair it correctly.

For example if the oil pan gasket has been installed poorly, they may be trying to just tightening it rather than replacing it.

I don't really want to knock somebody with out knowing for sure. It is possible to make mistakes, I know I have at times. But being an auto mechanic myself, I do know that there are plenty of others that do not take such pride in their work as they should.

You may want to take your vehicle to another shop just for a second opinion on what the leak may be, or be more inquisitive by taking the vehicle back to the place it was worked on - ask what they are finding out, and what is needed to remedy the problem.

If they are truly a good shop, they should be truthful, and not give you a run around...

The oil could be leaking from anywhere. You need to get under the truck and see where it is dripping out. Once you see where it is coming from, take it back to the mechanic who rebuilt it and tell him to fix it. You did get a warranty, I hope? If you know where the oil is coming from he won't be able to BS you about it.

Edit 1

Replacing a gasket with a higher priced one? If it was put in right to start with it wouldn't be leaking.

Edit 2

Oil won't leak from the chassis. It is dripping onto the chassis from somewhere up above.

Edit 3

Fuel cleaner won't keep your engine from rattling. If the machine shop shaved your heads or did something else to increase the compression ratio, you may need to run with a higher octane.

Honestly I would not take my ride back to the same **** stick who couldn't do the job correct the first time. The Tensioner will only run you about 40 bucks (I bought one for a 96 s-10 blazer). it's very simple to replace and will take about 15 minutes to do, Sounds like the machine shop and/or the mechanic did not replace a plug or used too much silicone. That is a repair HE NEEDS TO FIX,since he peformed the repair. You already know this.

I know shops can be busy, but it should take about 3 days roughly to do. But I have seen and done it in a day. If you have any more problems call the Better business bearu and report said business.

Dave is right! A gasket properly installed shoud not leak. A problem I had with my Blazer was the oil coolant line. It is a high pressure line and can;t be repaired,it must be replaced. Cost is about $200

who ever rebuilt the engine is responsible for what they under warranty. If it`s leaking in the middle of the engine where it bolts to the transmission , it is the rear main or oil pan gasket. If either is incorrectly prepped or incorrectly installed it will leak. which falls under warranty work. When it comes to your rattle noise get a soft face hammer and hit your catalytic converter at the clamps and see if you can get it to rattle.

it sounds like a rear main seal leaking on it,basically they might not have did their job good enough,because a new rebuilt engine should not leak any oil ,id take it back ,and tell them i didn't want it back until it was right this time,they may have to use a sleeve on the rear main seal if it was wore some they,ll never get it to stop without sleeve it,but make sure they fix it right this time,good luck with it.

it sounds like a rear main seal leaking on it,basically they might not have did their job good enough,because a new rebuilt engine should not leak any oil ,id take it back ,and tell them i didn't want it back until it was right this time,they may have to use a sleeve on the rear main seal if it was wore some they,ll never get it to stop without sleeve it,but make sure they fix it right this time,and dont forget to change your air and fuel filters too,good luck with it.

easy way to tell wher ethe leak is put a big piece of card board under the vehicle. then with a flashlight see if you can see where it is coming from. but just being rebuilt the mechanic is liable. there should be no aditional cost to you . if he tries to. get a lawyer.

Make the mechanic check it. It may be a bad rear main seal, if not put incarefully they tend to leak.

valve cover gasket or the oil pump. try steam cleaning the engine and try and notice the area which first gets dirty. try just tightening the valve covers first...as the gaskets may be just fine...if they are there. no silicone, use real gaskets.