M5R1 trans problem

[stuman7981]

I have a 1994 Ford ranger 4.0, 5 speed trans, manual transfer case. I got the truck in Jan 2009. I put in a rebuilt transmission the same month. Now the trans is making a growling noise in the rear section. You can hear the noise while driving the truck and it almost disappears when the trans gets warmed up. I only have 20,000 miles on the trans. Is it the rear bearing going out? What else could the noise be? Now for the biggest question. Can I remove the rear section of the trans while it is in the truck to replace the bearing or what ever is making the noise or do I have to remove the trans completly from the truck? What other upgrades can be done to this trans? I have heard of the 1-2 synchro update but have no idea what it is about. What was the R-4 trans? How new of a trans could I put in my truck? Would it be heavier duty then what I have now?
Are these trans durable or do they have a bad rep? Thank you for all the help. Sorry for the ton of questions. Thanks again.

 

[chrwilkins30]

from what i've heard they are the strongest.

 

[vanmor]

I rebuilt my M5R1 last summer. I did make a couple of mistakes but learned a lot.

First, my 91' Ranger is 2wd. I'm not sure if you have to remove the transfer case but I imagine your would. Second, you can work on reverse and fifth gear in the truck with the tailshaft housing removed. Anything more than that, you will have to remove the transmission. Don't be fooled by where the noise is. The problem can be anywhere in the transmission and the noise just appears somewhere else.

Are you running ATF in the transmission. Check your level. If it's low, top it off and see if the noise goes away. I am using 5w30 synthetic motor oil in my transmission now. If your using ATF, you might try draining the transmission and replacing it with synthetic motor oil like me. It's a little thick on some really cold mornings, but it quickly warms up when you get moving.

Also check you speedometer gear if you have one.

These simple things may make the noise go away before you start digging into the transmission itself.

 

[The_Dealer]

id check the level of the fluid, maybe add some lucas to it