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Stripped oil pan threads

Do oil pan threads just eventually come out on their own or is it more likely the fault of the party changing the oil. I.E. overtightening of plugs, crossthreading,…etc?

It’s because someone, at some time or other, tightened the oil plug too tight or crossthreaded it. The last person who changed the oil might not be at fault. There are several options to repair this condition. Check them out at your local auto parts store.

I see it all the time where the drain plug was overtightened. The threads, instead of being at right angles to the shank of the bolt–or actually–the drain plug–are slanted away from the hex end. People think that by cranking on the wrench it will seal better but all it does is warp the gasket or washer.

I’ve been changing the oil in my cars for more than 30 years and have NEVER had a problem with the threads in the oil pan or on the plug.

If the threads have been damaged it’s because someone cross threaded the plug and/or overtightened it.

The threads don’t just wear out on their own.

Cross threading or over tightening.

I’ve NEVER had this problem on any vehicle. I’ve had oil pans that had several hundred oil changes by the time I sold the vehicle.

The quick lube places are notorious for this.

With certain Honda oil pan threads they seem to wear out over time as Honda specs 33 ft-lbs for torque of drain bolt because there’s a crush gasket that must be crushed. I always use a torque wrench when doing oil changes on my car and last year the threads just gave and the plug continued to spin. I ended up replacing the oil pan. If the pan is steel you may be able to retap the threads.

Were you installing a new crush washer at each oil change?

Most problems are caused by overtightening which pulls the threads and eventually pulled threads may just give up.

Twin Turbo is correct about the use of a new crush gasket and I don’t understand at all why an entire oil pan is actually replaced or it is recommended that it be replaced due to thread damage.
That’s what thread repair kits or oversize plugs are for.

I agree with the Honda exception, every new mechanic was told by about every other mechanic to be very careful with the drain plug, myself I installed a new washer every time. I came to the Dealer experienced but still the lead tech just about had a coronary when he saw me using my air rachet for drain plugs, if you know your tool you can do things that would get others in trouble.

It is always the fault of a party changing the oil…but the poor guy who ends up with the stripped thread may not be tha same one that did the damage. It could have been a prior gorilla.

I’ve been changing oil for over 40 years and never stripped or cross threaded a pan. Some would say I’m lucky. Some would say I’m smart. Some would say I’m weak. I say I take precautions. I only use “stubby” wrenches to install plugs, to limit the amount of torque I can apply, I clean the plug and thread before reinstalling, and I take the time to be sure the threads are properly engaged. If it isn’t starting smoothly, I back out and try again.

Stripped threads is human error. Some cars are easier to cross thread than others, and some oil pans are “fragile” which makes it easier to do on one car compared to another. But in the end if the treads are shot someone messed up.

I’m curious as to why you asked. I’d like to add that if your threads were stripped, do NOT fall for the sometimes suggested “need” for a new oilpan. Stripped thread can be repaired with tapping and helicoiling or even with tapping oversize an dinstalling an oversize plug.

Some posters have faced this “need a new oilpan” diagnosis. That can be an awfully expensive and IS a totally unnecessary way to repair stripped threads.