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Oil Pan PUZZLER

My mom, who lives in another state, asked me about this:

She takes her car to a shop to get her oil changed a couple times a year. The last time the shop recommended an oil pan replacement. This time, they put the car up on a lift and showed her the pan’s bottom was wet with oil on the outside. Yet, my mom tells me her parking space has no oil leak signs AND her oil dip stick is right at the same level in between oil changes.

Even if she is not reading the oil dip stick correctly, then there should be oil stains on the pavement - even if there is only a very small drop leak. Or, does the oil drip-off only when the car is being driven, but not when it is parked? Weird! Any thoughts on this puzzler?

I’ll copy-n-paste the replies on this topic back to her in an e-mail. Thanks.

If it’s not leaking around the drain plug (they should use a new washer each time), not leaving puddles or spots, not dripping on the exhaust system and It’s not causing her to have to add oil then leave it alone.

Many cars have slow leaks that don’t leak enough to worry about. Sounds like you mom’s is one of them. Please remind her to say ‘no’ to that shop when they recommend flushes and other unneeded services. If it’s an oil change chain, she might want to find a good independent shop, check under “Mechanics Files” above.

Kudos to mom for properly monitoring her oil. Your mom is not “using” excessive oil, and she therefore does not need an oilpan replacement. Even if the WERE using excessive oil, and even if it WERE leaking from her oil pan gasket, she STILL would not need a new oilpan.

Lately it seems like new oilpans are the latest rage for less than scrupulous shops. We’ve had a number of people post the same story. This is a scam. Tell mom she was smart not to fall for it.

Even if it is leaking around the pan gasket it’s possible the bolts just need tightening, but before tightening them check the recommended torque, most oil pan bolts are very low torque to keep from warping the oil pan.

In addition, many of these bolts may be in “blind holes” and may be installed “bottomed out”, which means that overtorquing them manifests itself as broken bolts.

They are most likley recommending the oil pan beacuse the drain plug threads are on their last legs…as a tech I don’t want to be the last guy to tighten a drain plug that falls out because the threads are gone and they’re looking at me for and engine

The OP suggested that they made that recommendation because of oil on the bottom of the pan, however even if the threads were damaged the oilpan would not need replacement. Retapping for an oversize plug is far cheaper than a new oilpan.

Most over sized oil plugs are designed to re-tap the threads by simply inserting the plug. I put an over sized plug in my '88 Escort probably been 10 or more years ago and it’s still doing fine. $5. over sized plug vs. several hundred dollars for a new oil pan and labor. I’m going with the $5. plug. The garages that are replacing oil pans because of worn threads I bet aren’t telling the customer there’s another option.

"The OP suggested that they made that recommendation because of oil on the bottom of the pan, however even if the threads were damaged the oilpan would not need replacement. Retapping for an oversize plug is far cheaper than a new oilpan. "

Yes but you’re thinking like a consumer not like a shop. Might already have OS plug in sideways

Any shop that recommends replacing the oilpan because of oil on the bottom of the pan…or because of stripped threads…even if there’s already an OS plug in it…isn’t thinking “like a shop”. They’re thinking like a scam artist.

Except for Pumkinkrasher it looks like everyone began with the assumption the mechanic was incompetent, dishonest, or both. It’s not that the advice is bad but, given the overwhelming lack of information I don’t think it’s a fair starting point. The mechanic reported to mom, mom reported to son, son reports to CT. I doubt the whole story got through. Nothing is known about the car or mom. Maybe mom drove over a curb and the pan is cracked. Maybe the car is thirty years old and the pan is rotting through. Maybe the mechanic is a crook. It was too early in the process to tell. The OP should have called the mechanic to get the story first hand and been asked to provide a little more detail about the problem. Sorry, I don’t think mom will get the best advice out of this.

Hey, this may be off the discussion but I took my van to a Goodyear store today to have the oil changed. I drove it home and checked it out and the filter was leaking and a drop hit the driveway. So I went back and the man tightened the filter and apoligized and I went back home. But if I had taken off for a long trip I would have ran out of oil.
Until the last year or so, I did my own maintainence on my vehicles.

It could very well be the mechanic was incompetent. Without thoroughly cleaning all the oil off the pan and everywhere it splattered, it will be very hard to pin down the origin of the leak. I did actually have to replace an oil pan on a car I had. The car was an old police cruiser and the oil pan rusted out just enough for it to be porous and ooze oil. If the car you mention is about 10 years old, has been driven in the snow belt, and has never had the underside washed except for going through puddles, this can happen, assuming you don’t have a plastic oil pan. As someone else mentioned, it could have been damaged by running over something, or even someone that changed the oil could have cracked it by overtightening the drain plug, which happened to a coworker at a fast lube place.