I was doing a drain and fill on my 04 LS and I ended up rounded the 24mm refill bolt on the transmission while trying to get it off. At this point, I had already drained just over 3 quarts from the trans oil pan. Didn’t think to make sure that I could get the refill bolt off before draining. So now, my car is stuck on ramps in my driveway and I’m not sure how to get this bolt off. I only have about maybe 2 inches of clearance to get to the bolt, so I don’t think I can get an extractor bit in there.

Does anyone have any suggestions for how I could remove this bolt/refill the transmission? I’ve contemplated just trying to pump it back in through the drain port, but I don’t know how I’d get the correct amount of fluid back in that way. I’d prefer to not have to tow my car to a dealership tomorrow, but I’m not sure what else to try.

 

Is there anyway to get a file in there to reshape. Can vise grips reach to clamp real hard then turn vice grip? You are not the first to do this and it is an afterthought to loosen the refill first to make sure. Without the dipstick I don't think there is a way to make sure not overfill so the fill port has to be opened. I have used vise grips many a time on similar situations of a rounded bolt. Another to try is measure exactly what came out and pump same back in but not proper way. President of Aisin transmission company told me overfill, underfill, contaminants are what destroy transmissions.
This also happens on differentials quite often.
Another to try is grind the extractor tool down where it will fit.

 

The file is a good idea, I’ll try that. I tried with vise grips, but i couldn’t get a very secure grip on the bolt, and i felt like it was rounding it even more.

 

Try a 15/16” closed end wrench.
24mm = .944”
15/16 = .937”
The difference is negligible but the smaller 15/16 wrench might be just enough to grab on.
Also, when you get the wrench in place jam a thin block of wood against the wrench and plug. This will force the wrench to stay on the nut as you turn it.
As you mentioned there’s only a couple inches of space to work, use it to your advantage.

 

Get a socket that is a smidge smaller than the bolt and hammer it on

 

Not enough room for a ratchet and socket you have to use a wrench.
A socket by itself will fit into the tight space, a ratchet with the socket attached will not.

 

Buy a low profile socket that has a hex end so you can use either a box end or open end wrench to turn the socket. Search "Milwaukee square end socket", Olsa tools makes a set of stubby impact sockets that have a hex end for a wrench, Amazon carries knock off versions of the same stubby impact sockets that have a hex end.

 

The issue isn’t necessarily the tool.
The root of the problem is the shallow head of the fill plug. The hex section is less than 1/4” tall. A standard 24mm/15/16” hex nut is approx. 3x taller.
There is an underbody panel on both sides of the transmission with VERY LITTLE space between the two. Whatever tool you have that will fit into the space is still trying to grab a very shallow nut. You have to secure the tool on the plug so it can’t slip off. My post above (#4) is not a guess or a theory, it works every time. Find something to occupy the space next to the head of the wrench so it can only turn and not move away from the shallow head of the plug. Easy peasy 👍

 

JB Weld may be worth a try.

 

Genius!!! Worked for my gs 300 and I'll never take it off without it I used the end of my rubber mallet super stripped bolt

 

A long handled (e.g., 14 inch) 15/16 offset wrench works perfectly for the fill plug. No need for a spacer to hold it in place while torquing the fill plug.

15/16 offset wrench for the transmission fill plug.

 

So since we are diggin up old threads, how did this get resolved?