Redline MT or Gear Oil?

B1Toad

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For the manual transmissions are you guys using the Redline MT or the Redline gear oil? I noticed the MT is only GL-4 but the gear oil is GL-5 which the service and owner's manual both calls for.
 
Gl4 what you want
  • Many NV4500 truck transmission applications like Chevy Silverado and Dodge Ram, for Chrysler spec MS-9070
  • Safe for brass synchros, as it lacks the reactive sulfurs found in most GL-5 oils that cause damage
 
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Redline MT GL4. Use it in both of our jeeps and works excellent. I had a 03 wrangler with 5 speed nv3550 few years ago with 160k in it. Trans made tons of noise and hard to shift. Switched to redline Mt amd was amazed how much better it shifted. I am a believer amd worth the $$
 
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I've always bought two quarts and it starts to overflow towards the end of the second quart. I think there is some residual oil still left in the gear set.
 
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With all the rave reviews the Redline gets I wonder if it would be worthwhile to run it in the axles?
 
I replaced the pennzoil syncromesh in my ax-15 with Redline MT90 and feel that it is very notchy now. Ill go back to synchromesh at some point.
 
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Not a big fan of redline personally. I like Sta-Lube 85W-90 conventional GL-4 myself.

Kind of also want to try the Driven Racing Oil brand 80W-90 GL4 conventional sold at Summit Racing.
 
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With all the rave reviews the Redline gets I wonder if it would be worthwhile to run it in the axles?

I changed out the fluid in both my diffs, transmission, x case. Its a game changer- its as good as the oil filter change thread claims your mpg will be, better than rogaine for hair loss and duck repellent all in one bottle!
 
I've never used the Redline but I chamged y gearbox with Royal Purple Syncromax. I'm usually a RP sceptic but I'm very happy with the performance, smoothed out the shifting and not s much popping out of reverse. I appreciated that the RP was available locally