Transmission Fill Hole….

Ok.. this is probably a new one.

I went to do a drain and fill today on my transmission. And unfortunately when I pulled the fill plug the threads in case came with it.only thing I can think of is the last mechanic that did the service over tightened it and left it.

So here we are. I am thinking I can pull the front drive shaft, pull the pan. And helicoil the fill plug hole. Anyone know what’s behind the fill plug? Is there room for a helicoil?

 

What do you mean? It’s a 24mm bolt head. I think the threads are 18-19mm

 

I think I can pull the driveline. And if I need more space i believe I can pull the cross member and rear transmission support and lower the trans a little. Can probably also remove the cat and exhaust in that area.
Waiting for a helicoil kit that big to get here. I’ll update.

 

That sucks. Since there is no pressure in there and it's above the fill line, I wonder if there is some kind of expanding rubber plug, sort if like a bilge plug on a boat that would work if you can't readily helicoil it?

 

Not sure. Luckily I don’t need to drive it, I have another vehicle.

worst comes to worst. Does anyone know how difficult it is to pull the transmission?

i had to do it on a 94 pickup, and it was fairly painless.

 

I’m a fan of time-sert fittings, don’t know much about helicoils, but have had good success with timeserts in an oil pan.

 

Pulling the transmission should be easy, doesn't seem like it's much work just looking at it.

If I were in your shoes, I would use an expandable freeze plug, they're about 5 bucks and work well. You'd have to drop the trans for a proper helicoil repair, you have to get the correct drill bit and thread tap, then drill it, tap it, and install the helicoil. Another thing to consider, if you attempt it, is that you want your transmission with the pan side DOWN when you drill and tap it. If you rotate it pan side up (where it's easier to work with), then whenever you drill and tap, there will be at least SOME metals shavings that will fall into the trans that ain't gonna be found. And you don't want that.

I'd also stick a block of wood behind the hole when you go to drill it, just in case your drill bit punches through too hard, you won't damage whatever is behind it.

Drop the valve body to get more working room. If you plan on re using the filter, don't forget to grab another O ring gasket for it.

The arrow is pointing to the fill plug hole.

 

Imperial makes a better looking plug that does the same thing.
rated to 100 PSI.

www.grainger.com sells them. part number 140-F-10 will get you close.
https://imperial-tools.com/products/tubing-test-plugs/

 

I wouldn't want something sticking out of my transmission that far. The regular expansion plugs are almost a flush fit. The trans doesn't build hardly any pressure. A regular expansion plug will work fine.

But I really do like the product you posted, I could see alot of different uses for it.

 

Good Call on removing the valve body. that said do you really think the trans has to be pulled? I have the drive line and cat out already. I think if I drop the cross member I will have enough room with a 90deg drill.

 

Welcome from NY.

 

If you have a 90deg drill you should be good. I assumed you had a regular drill.

 

Your a fool to get metal in the transmission which you will. You won't think you will but you will. Use the expansion plug. Done. Permanent repair. By the way Makita makes the smallest right angle drill on planet, work of art. No battery but 110v

 

No way would I pull the trans for that. An expansion plug will work perfectly for that, since there no pressure their anyway

 

Interesting to come across this.
Dealer jacked up my threads then said they were like that when they pulled the plug. Which is odd given they are the only ones to touch it. Either way, they played the blame game, so I took it to a local shop. He threaded it with pipe thread similar to the transfer case. Did an awesome job. That seems simpler than a helicoil.

 

See if anyone makes a self tapping oversize drain plug for that size. When I worked at shops years ago we had a bin of oversize repair plugs. Like 14.5mm and 1/2" single oversize and double oversize.