Loose Mounting Stud

[Newtwo6x6]

I have a T20 transmission, Max IV. I thought it was just that a nut was loose on the stud, but it is the stud that is loose. If not fitted properly it will just loosen up again went driving the machine. What do you think? Back the stud out some and put some Loctite on the treads. Or should I completely remove the stud and remove the nut then install the stud with Loctite. Also what grade of Loctite should I use?

[hydromike]

This will take some investigating to make sure the threads in the aluminum T-20 case aren't damaged. What tends to happen on some machines, is that the stud will work loose out of the case, and the transmission can rock back and forth (even just a tiny bit) which often ends up destroying the stud hole in the case. Take the stud completely out, and inspect the hole in the case for damage. I know it's basically impossible to see it (especially on a Max IV), but even if it means pulling the transmission out completely, it'll be an investment worth making. If the threads don't *look* too bad, chase them with a 3/8-16 bottom tap to clean them up once and then test fit the stud again (or just a bolt) to see if it tightens up ok. If so, and you feel confident that the case isn't weinered- out (can I say that?) I'd replace the stud with some red Loctite. It'll be good to take a look at all the other stud holes while you're at it. Heli-coiling a case or welding/retapping is a much bigger job. Hopefully you caught it in time.

[Newtwo6x6]

Thanks, Hydromike, I will get a tap and check it out. Hopefully the stud hole threads are good. Removal of the transmission doesn't look like much fun.

[amphibious drew]

I just put helicoils in half the holes in my t-20 for my Max IV. It's not that bad of a job at all. Pulling the engine and t-20 is about the worst of it. Just make sure you use the correct bit and tap for the helicoils if you go that route. I believe the bit is a 25/64. I bought one at fastenal as it was the only place in town that sold the bit. All the auto parts stores sell the rest of the kit, but not the drill bit required to use it.

[Newtwo6x6]

Thanks for the help. I was able to re-install the stud without removing the transmission, the threads were good, I chased them with a tap and installed a new stud with Loctite. I checked the other studs, two are good. The other one the nut seems to be rusted on, so I will leave it as it (the stud) is tight. I will just have to check it as part of my routine maintenance. Repair the stud when the trans has to come out.