Oil Pan Drain Plug

I have a 2000 Grand Caravan and had a Chrysler dealer change the oil in July…just took it in today for another oil change and they told me the oil drain plug just turns - either the plug is stripped or the threads on the pan are stripped…I said that they were the ones who changed the oil last time so if anything happened then they did it…they are saying that over time the threads can become stripped - suggesting that if the threads on the oil pan are stripped then I will have to buy a new oil pan…I said that I had not touched the oil pan so if something is wrong then they are responsible - the threads don’t just strip themselves…any thoughts?..thanks

Oil pan threads can be easily fixed with a thread insert or an oversized self-tapping drain plug.

Those threads do NOT strip or wear out over time unless someone manhandles them. That is a ludicrous statement you were given.

If they’re stripped then some ham-fisted lube tech at that dealer either overtightened it OR in the event that someone else in the past caused the problem then the dealer lube tech should have been aware of the problem and brought it up before instead of running the vehicle out the shop door with an iffy drain plug.

The threads on a 14 year old car can be damaged a little each time and finally give out. There is no need to replace the pan, there are all sorts of products that will fix it, the simpleist is an oversized thread cutting drain plug.
To get the old one out, just lock a vise grip on it while rotating left and pulling.

Common problem.

Aluminum oil pan with a steel drain plug. Over time the steel drain plug will stress the aluminum threads in the oil pan each time it’s tightened to where it strips the threads out of the oil pan.

Steel is much harder than aluminum

I’ve seen this so many times I found a local source for this oil pan thread repair kit.



at least your oil didn t all leak out.

I would consider myself lucky to have escaped so cheaply.

you don t need a new oil pan, but the dealer really isn t the place to take older cars you want to keep

Most pans can be repaired with a Time-Sert while on the car. If it has an aluminum pan the Time-Sert will be better than the factory threads. If the car has high mileage they may charge to put in the insert, but it is cheaper than a new pan. When I have this happen I just install the insert and ship the car. For me the time wasted trying to sell a repair is not worth it. I have my own insert sets and I can do an insert in about 5 minutes. In my opinion Time-Serts are the best way to repair oil pans, and any threads in general. Ask your dealer if they will install one and you will be good for a long time.


If the dealer will only install a new pan…and refuses to put in a time-sert, then find an independent mechanic that will.

I’d also let them know in no uncretain terms how disappointed in their services you are. I’d even mention that I was concidering on looking at new cars, but with this eppisode…you would not concider dealing with them.


I currently own a 26 year old car with almost 300,000 miles on it and the oil pan threads are as straight and clean as new. We sold our Mazda with an aluminum pan, 265,000 miles, oil changed every 5,000, and those threads were also pristine. Trashed threads doesn’t come from wear, but from oil change monkeys being ham-fisted and otherwise careless. Most oil change places and even dealers put the least experienced and barely trained young people on the oil changes. Shops like JL have a high turn-over rate. Adequate training would be too expensive, so they teach a crash course and set aside part of the profits to pay out damage claims instead.


I respectfully disagree with you

Over the years, I’ve encountered plenty of worn threads in aluminum components, which were NOT due to some ham-fisted guy

Like the others have said, sometimes threads in an aluminum component just wear out over time. I’ve also seen this happen on aluminum transmissions, specifically the female threads for the pan bolts

@db4690, then we disagree. I typically keep cars until the wheels fall off and have rarely had aluminum threads strip out on any of my cars that I maintain myself. The only time I had a stripped thread in recent memory was a rehab car that was pretty worked over before I got it. I do deal with stripped threads a lot on other cars that other peole have worked on. So, I stand by my statement.

The secret of not stripping out the threads on aluminum oil pans is don’t try to remove the drain plug while the engine is hot.

But most quick-lube places remove the drain plug as soon as the vehicle is pulled over the pit.

This is why they recommend that you allow an engine with an aluminum head to cool down before attempting to remove the spark plugs. Because you can take out the threads in the head.


I’m in the don’t blame the dealer for the condition camp- things wear out; but also don’t buy the dealer’s solution of a new oil pan either. The threads on the plug of my "96 Breeze were worn badly after 15 or 16 years of me changing the oil (and I don’t think I’m ham-fisted)- but with a new plug I had no leaks- from the pan. Lots of other places, but not the drain plug.

Guess I will remain one of the odd men out but I agree with BustedKnuckles and don’t buy into the theory of aluminum threads wearing out if any overtightening is not involved.

There are century old aircraft engines which have never suffered crankcase plug and spark plug thread failures and Lord only knows how many times those have been out over the years.

The old era Subarus used to get head bolt retorques every 15k miles and even with 70 Ft. Lbs applied there were never any issues with threads pulling out of the aluminum blocks. It was also recommended that they be retorqued while the engine was warm.

My roughly 70 year old Harleys have never had any issues with aluminum thread wear on the timing plug, crankcase plug, or spark plugs and back to the Lord only knows part of this; I can’t even begin to remember how many times those have been out in the 40 years I’ve owned those bikes much less the prior 30 years of ownership of who knows how many ham-fisted owners.

In the case of the OP they’re being told this by the same dealer who says the pan can’t be fixed and they need a new replacement.
It’s also the same dealer who apparently ran the car out the door just a few months ago with a problem.

I absolutely agree with those who say the threads were damaged by some ham fisted monkey.
I absolutely disagree with those who consider it normal wear.

In 45+ years of changing plugs on all manner of oil pan, including aluminum ones that I’ve been changing oil on for hundreds of thousands of miles, I have never stripped a plug out.

The dealer gave you a “song & dance routine”. This idea that it’s normal wear and tear is BS. The threads in the pan and the plug are both covered with oil when the plug is reinstalled after every change. This is not a dry installation. Them telling you that you need a new pan is super BS. In addition to an insert already mentioned, it can also be tapped out oversize. If these morons can’t or won’t fix it, have 'em put an expandable runner drain plug in it, fill it with oil, and get it to a real shop. An independently owned and operated shop. Then never darken the door of that dealer again.

Yes, you can and probably should print these response. I get so aggravated when dealers try to tell people they need a new oil pan because the threads are stripped… and especially when the dealer is the one that did it. If they’d been stripped out to the point of rotating freely before you drove in there you would have lost your oil. Or you’d at the very least have noticed excess oil usage and probably puddles in your garage. When the engine is operating, the oil in the pan is pressurized by blowby, and there’s no way you would not have been losing oil with a loose plug.

And now I think I’ll take a nitro pill…


I also stand by my statement


I’ll list 2 engines which are known for having stripped threads in the aluminum block . . . the female threads for the head bolts

Toyota 2AZ-FE

Mercedes-Benz 116

I suppose the guy assembling the engine at the factory was ham-fisted?

I’m just making a point

Please don’t take this the wrong way

I have a 2AZ-FE engine with over 217,000 miles. I change my oil every 4K to 5K, which means I’ve changed it at least 43 times. And it still threads in snug and sure.

I changed my oil on my '89 Toyota 22R engine at least 84 times over its 338,000 lifespan. The plug still threaded in snug and secure when the truck was totaled in an accident.

I drove my '79 Toyota for almost 11 years and the drain plug in its 20R engine still threaded in snug and secure when I finally gave it up due to frame rot. I lost track of the mileage. I probably changed the oil at least 60 times. Maybe much more.

I could go on, but you get the point. If drain plugs are properly installed and not overtorqued the threads do not wear out. As I said earlier, this is not a dry installation; both the plug and the pan threads are covered with oil.

problem is, I only change my oil when my engine is hot. maybe I could break the plug loose, snug it back, then take a 20 min ride, then change the oil.

in my old truck, I can just crank the plug tight, no worries.

I was very careful with the jeep. the threads seemed flimsy in comparison. pretty sure its steel of some sort tho.

This has bugged me since the very first time I saw it done. Who in their right mind deploys a design where the sacrificial part is on the hard/expensive to replace end?

If the bolt was always a softer material than the bung, it would be more likely to strip first. Then you simply toss the bolt in the trash and replace it. A 5 minute, low cost problem versus…

The head threads stripping out is a defect in materials or improper process control at the time of manufacture. It’s not a repetitive (mis)use failure.

There’s a difference between a design flaw and worn threads due to repeat ins and outs with the latter being claimed to be the case regarding the OP’s vehicle.
If removing and reinstalling a perpetually lubricated drain plug will wear out the threads then I have to wonder how in the world the camshaft journal surfaces on aluminum heads last more than 5 minutes with constant high speed friction and pressure applied to them.

I don’t believe the OP mentioned the engine option but who says the pan is even made of aluminum? At this point that may be nothing more than speculation and was not from me.