I build trannies here. I was using syncromesh in my 600hp car till I saw the effects it has on gear surface. You can listen to all these good reports that dont amount to any proof. Or you can listen to the advice of tranny expert who has seen the destruction of gear teeth with my own eyes.

 

Is using straight BG synchroshift II as bad as using straight gm sychromesh?

I've used straight BG II in my DD for around 10k miles here with very little abusing the car. I plan on changing this out to amsoil anyways because i know they make killer products.

 

I havent run BG. I use royal purple gear max.

 

I used BG in my DSM for about 70,000 miles and it would drain looking as good as when it went in. So, I decided to try GM Synromesh, it was recommended by many DSMers. My transmission started to go sour within a couple of thousand miles - started to make noises that convinced me I needed to do some soon in order to stay on the road. Since I couldn't get the unit rebuilt "right now" I went with a new transmission from Mitsubishi - about 2K.

 

so I use 2qts gl4 rated gear oil and can I still use one qt gm synchromesh then?

 

I use straight redline mt90 gl4.
25k miles, 350whp, beat the **** out of it drag racing every weekend. I had the trans taken apart and inspected, no problems at all. Putting new sycro's in for the hell of it. Switching to this from stock, made a HUGE difference with shifting, million times better. All my evo/dsm buddies use it too, no problems because of the oil.

 

u guys think that's why im grinding into 5th cause I used mobile one gl5 rated? Im gonna use mt90 and see what happens from there

 

GL5 oils are corrosive on bronze syncros. Most gear oils at your local auto parts stores are usually only GL5 oils.

 

Will the mt90 help my grinding issue? Gonna drain out that stupid mobile one and fill with mt90

 

I guess i ask why on earth would you do this? to save a few dollars?

 

to save a few dollars? I used the wrong rated oil and now i wanna see how mt90 performs. I hope the grinding issue was due to using gl5 rated oil. I just hope the redline mt90 will shift better

 

I was only curious as i paid A lot for Mits Tranny Fluid and was told never use anything else. I use GM in all of my GM's, I have 3 of them. Mits oil in the Mits.

 

understandable