Muncie M-2....Red Line gear oil = smoother shifting?

[Tantrix]

I have a 76' C10 long bed with the 3 on the tree that I converted to floor shift since the column shift was shot. The truck sat up for 14 years before I bought it, so I flushed the trans twice before I began driving it daily.

It doesn't grind gears, but is difficult to get into 1st or reverse gears from a complete stop without going into 2nd or 3rd first.

I have some cheap Coastal SAE 80W 90 in it now, but I have heard that putting some Red Line MTL or MT-90 in the 3-speed Muncie M-21's could possibly clear up the rough shifting I'm experiencing.

Anyone dump cheap gear oil for Red Line and have shifting improve in a Muncie? Also, which Red Line would be better for the M-21...the MTL or the MT-90?


Thanks in advance guys.

[N2TRUX]

I have heard good stuff about Redline and Royal Purple. Can't give any testimonies though.

[Tantrix]

Originally Posted by N2TRUX

I have heard good stuff about Redline and Royal Purple. Can't give any testimonies though.

Same here...heard good things, but never actually tried it. I've been digging around on the net for Muncie + Redline info, and apparently the GL-4 stuff is recommended for Muncie trannys.

I'm either going to try that or just have the entire trans rebuilt. Like I said before, it's not grinding gears but it's a pain in the ass when you try to take off from a red light and the truck fights me when trying to get into 1st gear. I'm almost tempted to just drive it using only 2nd and 3rd...

[billnorman]

Sounds like the clutch is dragging. Either needs adjusting, has oil on it, or has a piece of debris on it. It could also have a dry or worn out pilot bearing.
A real outside possibility is rust on the flywheel or pressure plate which will disappear with use.
Bottom line, adjust it, and if it doesn't stop grinding, pull the box and inspect it.

[884x4Sub]

A long time ago I had a Nissan 280zx......I was a long way away from home once on a Sunday and the clutch slave cyl went....I drove all the way home with no clutch.....after I got it fixed it would grind a touch going frm 3rd to second and a little more going from second to first......and once in awhile btween first and second......never did it before.

after a month of this I drained the tranny oil and put in Slick 50 (if I remember correctly at the time they reccomended using the standard motor oil in manual tranny's).....anyway a week later all grinding gone...changed it again anyway, had the car for another 2 or 3 yrs.....no grinding

[swb85]

billnorman is correct, your clutch is dragging. A fluid change will not fix this. As far as fluid goes, older transmissions with brass synchros need GL-4 gear oil. Napa keeps GL-4 in stock, that's what I run in my M21.