I made a attempt at changing the fluid in my transmission, but I couldnt get either one of the plugs out of the transmission.

So far I've tried.
18" breaker bar (broke the 1/2 to 3/8 adapter
Soaking in PB blaster
Small Battery impact

I'm a little afraid to try heat, or a real big impact, so what do you all recommend?

 

5spd I assume. I would soak with pb more. Then a small propane plumbing torch. Steel in to aluminum never cooperates. Should come right out. I'd fill from the top. Pull the shifter and fill.

 

I had the same problem. Rounded both off almost completely. I picked a socket that I could hammer on and have some bite still. Then we heated the head of the plug up cherry red, hammered the socket on and it was like butter coming out. Don't over heat and don't impact and you should be fine.

 

Heat will do more than PB. Penetrants are for rust; these threads are seized due to the metallurgical mojo between the dissimilar metal (not the same as oxidation). Impact will be less likely to round the heads than long-arm leverage, but a longer arm, and a better quality adapter, might be in order.

On re-installation, use some anti-seize on the threads; always good to use on hard steel threads into aluminum castings.

 

impact + Aluminum = bad.

 

Well I ended up getting the bottom plug out with a combination of heat and a big breaker bar. The side plug I had no luck with, so I filled the transmission from the shift tower.

Should have done that last time I did a fluid change!

 

Now 3rd wants to grind every time I shift into it, up or down. It seems to go away once the truck warms up.

Fluid is Amsoil ATF

 

How much did you put in. I'm running amsoil in mine with no problems on a rebuild. I'm running 5 qts to help with rollover growl.

 

4 quarts, my gear-rollover growl is gone now. I'm gona look into doing the pedal box bushings, otherwise I think my 250K mile transmission is probily done geting due for a rebuild.

 

If you have not completely striped out the fastener, take a torch and heat just the plug until it is just starting to turn red. Then take a regular wax candle, press it against the plug, and let the wax melt onto and around the plug. The temperature difference should draw it into the threads. Let it sit for several seconds (20 to 25) and then try and remove it. We use this to remove oil galley plugs from engine blocks at the machine shop.

 

I'd say a little syncro wear.