Unfamiliar problem

I am unfamiliar with the name of the part I am dealing with, so I’ll describe it. However, I believe it is called the union bolt. Basically it’s the bolt my oil filter screws on to. Doing my first oil change on a recently purchased used car (2007 Prius), and the threads of this bolt are damaged, and I would like to replace it. Looks as though I can remove it using a 60mm allen. Is there anything I should be concerned with? Like does removing the bolt require additional work like taking off the oil cooler housing, are there torque specs, will I need air tools to remove it, etc. just anything I might come across. It really looks as though just the allen wrench will work, just want to make sure.

To start go on line to a dealer site that has parts diagrams. It will show the part and how it is assembled and provide the part number and price. Then you’ll see if you can replace the single part or the whole assembly. Air tools are usually only used to speed work or on very very big nuts like on an axle or crankshaft.

All I could find was a part number of 9090404004 and it was a single bolt with no diagram. I’ll keep hunting, thanks for reply

It’s called the oil filter union.



I think you need to re-measure. 60mm is over 2.25”.


Oops, I meant a t60 torx, wouldn’t accomplish much with a wrench that size.

Get the part first and then you can verify the size and if it is a standard torx or that odd ball.

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If I had that problem I’d let my local automobile machine shop replace the part. Given its functions and location, it’s the sort of thing where if your diy’er fix doesn’t take you’ll be looking at a big add’l expense. The machine shop will have the exact tools needed and they’ve likely replaced that part before, so they have experience. That experience is worth paying for imo.

Does your local machine shop have a lift? Perhaps you just bring them the engine, that is all that I bring to the machine shop.

And a good day to you, too.

Interesting point. Don’t machine shops have jack-stands and ramps for this situation?

I have never been to a machine shop with a lift. That isn’t the tool they need. You bring them parts for them to machine. They don’t remove them.

If the threads aren’t too badly damaged, some parts houses will loan out a thread restorer kit. It is tap and dies that are roll forming instead of cutting. They do not remove material, just reform it into the proper shape and they generally strengthen the threads at the same time because they tend to align the grain of the metal which cutting does not do.