stripped 10mm bolts on trans filter

Sounds like you might use some help on this suggestion: get an experienced person to tap out the holes to a larger size & use bigger bolts. Stripping bolts/holes is--excuse if this sounds patronizing--one of the 1st things a mechanic-in-training is taught NOT to do. Well, maybe safety should supercede. HTH & good luck--it's not the end of the world. BTW: tapping aluminum uses keresene instead of cutting oil. s

Actually there are cutting fluids just for AL. For instance, the one with the smell etched into my memory, TapMagic for aluminum.

Thank you for the response. I think I will purchase one of the helicoil kits from the local auto parts store and see which of the bits I'd like to use.

I thought one can just drill new threads into the stripped hole? I once tried to use a helicoil thing on a stripped spark plug hole, but I used a ratchet to re-thread, if I recall correctly. That was years ago and maybe I don't remember that too well, unfortunately. I don't recall using any cutting oil or kerosene.

It's alot easier and safer to use some sort of lubricant. True it should be the correct one for the metal, but I've found it's not all that cruical.

If you are going to drill it out and use bigger bolts you don't need a helicoil at all. Just drill and tap the next size up.

How badly are the threads stripped? I assume with AL they actually broke off and your choices are bigger bolts or helicoil. But if they are mostly there, you can get the correct tap and just chase them. That will straighten things out and cut away bent parts. Won't be quite as strong but should be usable.

Another solution would be to buy some 10mm studs and nuts. Put the thread locker on them and thread them in the holes. No threading or drilling required and they will hold better than a bolt, plus when you need to take it apart for the next change they will come off easier.

That is what I had intended to suggest. Sometimes if you drill and re-tap you get into trouble. Bolts can be too big for the filter, or you drill into a passage....that sort of thing.

Studs installed as you say can be the least risky approach.

10mm bolts are awful big for just holding a transmission filter in place, are you certain that is the thread diameter?

Also, since most transmission filters attach to the transmission valve body, I'd make damn certain of where I was drilling and tapping, that there is enough material on the sides and behind lest you totally mess up the valve body drilling thru a thin wall section of the valve body. Not a job to just dive into without a lot of investigation.

I'd like to thank everyone for the replies, especially the suggestion on using 10mm studs and nuts. I'm sure I'll have to cut the studs with a saw in order for that to work, of course, and it's a great suggestion.

As for the actual size of the stripped bolts, I took them off with a 10mm ratchet. They are probably 3/4 of an inch long.

I'd like to thank everyone for the replies, especially the suggestion on using 10mm studs and nuts. I'm sure I'll have to cut the studs with a saw in order for that to work, of course, and it's a great suggestion.

As for the actual size of the stripped bolts, I took them off with a 10mm ratchet. They are probably 3/4 of an inch long.

******************************* That is the nice thing about using studs.. .

First, of course, chase the threads with a tap. Go EASY. \ Just straighten the existing threads. Then you can prep the studs at just about any length, and fix them in place using LocTite

I have done this a number of times.

Use self locking nuts on the open end.

Do yourself a favor and learn a little about thread sizes and pitch. if you used a 10mm wrench size to remove these fasteners, odds are the actual bolt size in question is 4 mm, not 10mm.

Might also explain why you're having such trouble locating the correct thread insert repair kit.

Probably M6-1.0

Thanks. I took off the bolt with a 10mm socket, so I assumed the diameter of the opening was 10mm. I know there are different lengths to the bolts though.

Thanks. I took off the bolt with a 10mm socket, so I assumed the diameter of the opening was 10mm. I know there are different lengths to the bolts though.

There is more than that to consider, tysteel. The bolt head may have fit a 10 mm socket, but that does not mean that the threaded shaft of the bolt is 10 mm...In fact, it would not be, as a rule.

On metric bolts, you may also have several different "pitch" possibilities. Pitch is related to the fineness or coarseness of the threads...the number of threads per unit length.

So before you go back into that hole, go to a parts store or good hardware store and find out exactly what thread you have on the bolts. If you are going to "chase" the threads in the old hole, be sure you have exactly the right tap, and that you do it carefully. You only want to straighten and clean the old threads, not cut new ones.

If you want to make and use studs, you may find some clean threads at the bottom of the threaded hole. This will help your case if you can thread into some virgin territory. Look at the thread compounds, LocTite being a common and good quality brand. Pick the correct one for your application. As far as nuts on the end of your studs, choose a self locking nut, or again use LocTite

I'll bet a ham sam'ich that they are 6mm X 1mm pitch bolts. It is a virtual Asian standard to use a 10 mm head on their normal duty fasteners with 6mm X 1mm threads. I don't know of any other pitches used by auto manufacturers for 6mm width, but I have seen 11 mm heads and the like on some domestics.

Toyota MDT in MO

Agree 100%.

Don't know why I typed 4mm, fingers getting fat I guess.

10mm sounded a bit stout for a transmission filter though.

Not if this Hyundai Accent has the medium duty OTR transmission option with two speed rear diff! (Comes with the roof mounted pull-handle horn package)

Toyota MDT in MO

The strongest point, which both of you have made, is dont screw around with guessing. Find out what goes in the hole....for sure.

I have been very surprised by some bolt threads. If you are dealing with a sensitive area and soft alloys, check twice, go very easy...