I have read so many post's on NAM and other sites regarding what brand or type of manual trans fluid works best in their Gen I. Having rebuilt more than a few gear boxes and being an ASE Master Service Tech with a specialization in the highly competitive field of building competitive race cars, I thought I would do a test.


Keep in mind that I have not driven or owned a car with a manual transmission since the early 90's before getting my Gen I R50 with the Getrag 5 speed gear box. My car came to me with fairly low mileage (80K) and was truly driven by a most delightful school nurse. She babied this thing! It was spotless clean and VERY well maintained with every single penny spent or bolt turned documented and provided at the time of sale. Ive known this woman for some years and know her to be a very good MINI owner.


Back to the test.....


Obviously, it came to me with the OEM oil still in the gear box. No leaks, no failures and no problems, other than what I considered, some fairly sluggish shifts and a bit of gear/bearing noise when car was idling with clutch out, particularly when cold. Performance is crisp, just didn't seem to transition gears very smoothly.


My first test oil was Redline MTL. I observed an immediate difference in the shift quality. I found the shifts to still be crisp, but the amount of effort it took to get this thing into each gear was cut by about 50%. Very smooth gear transition. As for gear/bearing noise, it went quiet as a church mouse!


About 6 months later, I opted to put a Helix short throw shifter in this thing and again, felt fine, worked great, no noise. I started getting some low end clutch chatter so I figured it was time to get a new clutch. I was up near 100K and I haven't been babying this thing at all! When I put the new clutch set up in, I lost some fluid so I opted to just get a couple quarts of fluid and change the fluid again. I had to buy Royal Purple because that's what everyone around here carries. I got the MTL on amazon. I got it all together and started about the break in phase and my transmission immediately became quite a bit noisier than I had grown accustomed to. Gear shifts were very labored and just didn't feel very good at all! Cold with the clutch out it sounded like a time bomb under the hood!


Horrified by the Royal Purple, and concerned that something was wrong with the clutch swap, I made a call out to my local Amsoil salesman. He said he strongly recommended the Amsoil Synchromesh Transmission oil. Of course, I started doing my homework and lots of MINI folks said they loved this stuff! Again, No MTL available locally, so I put a couple quarts of Amsoil in there. defiantly an improvement, noise levels cut in half, gear shifts were OK, defiantly tolerable, but I was greedy! I wanted what I had before so...........


I took a 40 mile ride to a retailer who carried Redline Lubricants. I put the fluid in my transmission and VOLA'! Quite and smooth once again! I should add that its COLD up here! Temp in the teens for the entire time I have been driving with these fluids in there.


Each fluid was in that trans for at least 150 miles so I got plenty of time to experience it in all its forms. The Redline product provided me with the best all around performance with regard to noise levels and smooth operation.


I'm not taking anything away from Royal Purple or Amsoil, I use a ton of their stuff in race cars and tow rigs every single year. All I am saying is that in my Getrag 5 speed, Redline was the best for me! I still have the Purple in my power steering system and Amsoil in my crankcase and master cylinder.

 

Love the Redline MTL, I had the BMW on my 6 speed MCS and as soon as changed to RL shifts were sooo much soother and I have the factory LSD I may add...not that I know if it makes a difference. First time I used RL on my MInI was last summer, then my clutch went out so I put new RL again, then this winter due to the freezing temps and the fact that the car wouldn't shift into gear at first try I'm guessing that is the cold weather

 

Calumet City! Nice, drive by there everyday on my way from Oak Lawn to Hammond.

This has been the coldest winter I can remember. I still have my stock fluid in my trans but have 2 quarts of Redline MTL sitting in storage waiting for warmer temps to arrive for me to change it.

Glad to hear it worked best for you.

 

Switched to Redline MTL as well at 100,000km (around 62k miles). It did make a difference but it didn't fixed my lazy second gear synchro (Won't go in second gear when flooring it from a stop and shifting near redline). But otherwise, I recommend MTL, great stuff!

 

How many quarts does the tranny take? I just bought an R50 and want to change the oil in there.

 

thats good to know, i know the OEM oil doesnt appreciate being in the cold temps, around 14 deg F it starts to get rough for me, ill have to flush it know knowing there is better!

 

weird that they recommended synchromesh instead of the mt90

 

I changed out the factory fluid (120,000 miles on it) a few weeks ago with Redline MTL.....to be completely honest, I can't feel a single difference in how it shifts.

 

similar experience here - changed the fluid to Amsoil MT90 at ~95k miles, maybe just marginally smoother at best. Oil coming out was black as night though lol

 

I don't put much faith in a lot of the " best fluid" type reviews and tests people do. I don't consider " it shifts more crisp" and "it takes 50% less effort to shift" type comments...good, accurate data. Unless you are using specific test equipment to verify these comments, it's just personal opinion.

 

Less than 2 quarts

 

Should we stick to 75w-80 strictly or can 75w-90 work fine?

 

"Horrified by the Royal Purple"

Have an 05' S with 131K and have used RP since it had 7 miles on it. I immediately noticed a significant smoother shifting effort when I first changed it way back then. I will be draining and refilling it for the 3rd. time tomorrow; about every 45K. When I also change the engine oil I also notice how smooth and effortless the engine runs/sounds from before. My gas mileage will increase by 2 to 3 mpg for the first 7500 miles after (not just my opinion) but facts supported by a state of the art car performance reader. I read many negative reviews of RP and just don't get it other than maybe just haters pushing their agenda? I can't say enough good about all their products like the coolant & gasoline additives that I have found made significant and profound improvements to my MINI's running condition. BTW, my Getrag transmission is a 6 gears; never heard of a 5 gear for a MINI? Maybe R50's are different? Not sure.

 

I changed the factory fluid with Redline MTF at 50k, with no noticeable change in shifting effort. The factory fluid was as clean as the new original fluid. Had I known this I wouldn't have changed the fluid.