What type of MTX fluid should I run?
What type after break in?
I recommend regular ATF+3 for 500 miles or so.
Any break in material will be minimal but it??s still a good idea to remove it. Also this cleans any particulates that may have gotten into the case when it was apart or even had open areas. (shifter tower, axles, etc)
I would then switch to Redline MTL. I feel this is the best choice because it offers the protection of a gear oil and has a viscosity between ATF and the Ford/MT-90.
You could also run Redline MT-90 which is a direct cross to Ford's honey fluid. However you give up some cold weather shifting ability just like the Ford fluid.
What about the Ford ??honey? Fluid?
The new Ford "honey" fluid is a quality product however it is much more expensive. You must also use the FM (friction modifier) with it and that makes it easily 3 times the cost. Not worth the money with the other quality choices available.
Other Recommendations?
A few folks have tried Pennzoil's Syncromesh with good results. It is a better quality version of GM's Syncromesh fluid.
It uses Pennzoil??s Pennzane which is an exceptional base. Under $5 a quart is also about half the price of GM??s fluid.
Like with the Redline no FM is required.
Why not ATF?
ATF does not have the sheer strength required to withstand use in a manual transmission therefore it breaks down very rapidly. When the fluid breaks down this means loss of adequate fluid supply for the syncros. That leads to excessive wear and premature failure.
Yes ATF gives that nice shifter feel ??instantly? so customers don??t complain but the transmission eventually will. I??ll live with my 10 second preflight rowing of the gears and blipping the throttle. It??s good preventive maintenance away.
How often should I change my MTX fluid?
Any non-synthetic gear oil or any ATF should be changed every 1 year/15k miles.
Any synthetic gear oil should be changed every 2 years/ 30k.
If you really do not drive your car ??hard? you could likely extend the intervals 50%. You folks need to get with the program though.
Either way it??s not very expensive and fresh fluid always makes the syncros happy. Not too mention that preventive maintenance is always a good idea.
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