Transmission fluid change

Does chevy recommend to not change transmission fluid? The drain bolt wouldn't come loose with a 3/8inch impact and rounded off with a 1/2 inch impact. The mount bolts for the shift linkage which uses a torx rounded out. I was able to remove one bolt with a pair of channel locks and move it out of the way. This allowed me to drop the pan. I used a regular bolt to reinstall the mount in place. I plan on using a ziz wheel to resize the drain bolt to a 14mm or 13mm so it has a full length fit for the socket. I plan on changing fluid only when I do my next oil change. How much loctite are the using for these drain plugs to prevent fluid changes?

Mine was the same way, and a coworker of mine said his was also stuck. I just removed the pan and did it the "old fashioned" way (and made an old fashioned mess!) I did notice a really big fitting on the inside of the pan that the plug threaded into. I wonder if that absorbes so much heat that it has to cool down completely before you can get the plug out? Considering how hot transmission fluid can get that could easily take a few hours.

They do this delibertly so you will go to a dealer. They use gobs of loctite to make it hard to get out. Look at how the drain plug is made about 14mm at the top and 15mm at the bottom. It is tapered and if you don't have the impact real tight it strips. If you don't have a ziz wheel use a file and make straight 14mm sides so you can get a full grip with the socket. The plug has a o-ring under it and doesn't have to be real tight. I talked to a friend at a transmission shop and he had the same problem. He just bends the bracket but I used channel locks and removed the back bolt and moved the mount to drop the pan. I used a regular bolt so it will come out easily the next change.
You might try a worn 14mm impact socket and tap it on and use a new bolt.
They also make extractors for rounded bolt heads. You know what to face be prepared the next fluid change. Try a different idea each oil change. If it comes loose just retighten it and you will be ready the next time.

I rounded mine off too. Apparently, the trick is to use a flared socket on it. I also rounded off the torx heads on the shift linkage b/c they are at a stupid angle to get at. Now I just use a pry bar (1/2" drive wrench works well), and bend it out of the way so that I can drop the pan.

I looked for a specialty socket from lisle but couldn't find one. I also checked otc.

There was a post a while back - a step by step on how to change tranny fluid. It also contained a discussion of the socket. Might want to try a search.

Too much work and too messy for me. I guess I'm just getting lazy. I just take mine to a Transmission shop I trust and they do it for me....

There was a post a while back - a step by step on how to change tranny fluid. It also contained a discussion of the socket. Might want to try a search.

Here is the post showing the socket to get http://www.automotiveforums.com/vbulletin/showthread.php?t=680954

//2000CAYukon

The mount that has two torx bolts takes a T35 Torx I'm almost positive. I did a yahoo search and lisle makes one just came out. I tried a T30 and it wouldn't loosen the bolt rounded out the inside. It just felt to loose and a T40 wouldn't go in. I took the old bolt I saved put it into a vise and I could use a small ball peen and tap a T40 into the bolt. Use regular bolts to replace and a 1/4 inch socket it will save you problems.

Yes, the shift cable brackets are T35. Hard to get to when they're on the TOP of the pan rail, vertically-oriented and in the tunnel.

I have also rounded off two of these pan drain bolts. No problem, I just did the messy pan drop operation. I also put a separate drain plug in one of the pans.

I went to Atlanta today on the way I stopped at Pep Boys,Napa,O'Riley's,and Advance Auto Parts trying to purchase a T35 Torx. I found you can't even order one. http://www.eazypower.com/wrk/subcatagories.asp?CategoryID=8
has them for around $2.50 depending on the grade. These are contractors quality. Click on Tee*@ Impact or power plus bits. Be aware they charge $10.00 shipping. I bought 5 different bits same shipping charge. They make metric allen heads and other security bits. Find some friends and split the shipping. Howard's True Value Hardware handles the brand. Northern Equipment Company sells cheap security sets which probably have a tamper proof T35 in the set. Use a search engine and type in vim Torx T35 they have a cheap 250 piece set for around $10.00. Lis26450 has one in a $60.00 plus set.

I contacted [email protected] he said nobody has any problems. Anybody who wants a T35 Lisle email him. He said nobody has problems with the drain plug .010 undersized plus tapered. If anybody wants a 1\2 inch Lisle drain plug socket that fits the drain plug properly email him.
I would especially appreciate Chevy mechanics to back me up. Even if Snap-On,Mac or Matco make them, help out the weekend mechanics.
Thanks Richard
P.S. GM parts says buy an aftermarket drain plug.

I pulled my drain plug today my pan was in two pieces. The large nut is just put in during a stamping operation. It is not magnetic and as I changed fluid a couple of weeks ago I wasn't planning on pulling the pan. The nut is torqued in and is slightly drawn in I used a 15mm extractor with a long 1\2 inch ratchet, It made the head round. I then took a 9\16 inch extractor tapped it on and used a 3\8 inch air ratchet and let it hammer until it came out. I pulled the pan and used a late model oil drain plug for Chevy's from Napa $3.99 12 x1.75 thread. It has a large black gasket on it Auto Zone's plug had to small of a gasket in my opinion but only $2.99. The transmission mount bracketts takes two 8x1.25 bolts about 1 inch long. If I was doing it again, I would pull the pan and use a small electric or air grinder cut the head off until it starts to crack tap it with a chisel. If you try to drill put the nut inside the pan in a vise drill out and use a 14mm drain plug. Reinstalling when it is a two piece set the nut into the slot so it won't turn then turn a new plug in by hand then use a box end wrench and tighten till it feels correct about 10ft lb to 15ft lb. The nut has a small nut which fits into the cutout in the pan. This is the same thickness as the pan. No leakage was observed after filling and running the vehicle until it was hot.

I replace my tranny oil back in the fall. I also stripped the drain plug. I had to get a nut remover from Sears and thrashed the existing bolt and had to replace it with another one. As for the linkage I used a 18 inch prybar and moved the linkage out of the way while I pullled the pan out. It worked for me as I could not get to the torx bolts atop the tranny to remove the linkage. I know that is not the correct way, But it worked for me and I have noe other problems. Make sure that you do not damage the pan flange at all.

I also did the 'move-it-out-of-the-way-with-prybar' technique - but LEARN FROM MY MISTAKE - make sure you remove the shift cable from the bracket first! I discovered the hard way that it costs $200 for a new cable from GM for a 4WD.