Hi all,
I have a 98 Ford F150 with the M5OD-R2 manual transmission. Ford specifies Mercon (now Mercon V since they no longer make Mercon) for this transmission. I've used various brands of Mercon and Mercon V (mostly Valvoline since I get it at work) in dino and synthetic versions. I've also tried Royal Purple Synchro-max at the recommendation of an online Ford truck club. None of the Mercon (or Mercon V) variants have provided consistent performance as far as I'm concerned. They are decent when cold, but once the fluid heats up the shifting is terrible. The Royal Purple was junk all around and I drained it out within 1000 miles. I've never grinded so many gears in my life as I did with that fluid.
I realize this transmission is not meant for butter smooth or fast shifting, but it seems to be at least acceptable (if not better) when cold (when the fluid is thicker).
Is there any recommendation for an ATF (or something that is compatible) that is maybe on the thicker side than a typical Mercon? I know that gear lube that is typically used in manual transmissions basically destroys the insides of the M5OD.
Whatever fluid I use I seem to have to drain and fill in about 7k-10k intervals as this transmission seems to shear any fluid very quickly. By about 5-6k miles there is a noticeable difference in shift quality from when the fluid was new. So if there is a fluid that should last longer, I'm open to opinions.
Thanks in advance for any help.
I have a 98 Ford F150 with the M5OD-R2 manual transmission. Ford specifies Mercon (now Mercon V since they no longer make Mercon) for this transmission. I've used various brands of Mercon and Mercon V (mostly Valvoline since I get it at work) in dino and synthetic versions. I've also tried Royal Purple Synchro-max at the recommendation of an online Ford truck club. None of the Mercon (or Mercon V) variants have provided consistent performance as far as I'm concerned. They are decent when cold, but once the fluid heats up the shifting is terrible. The Royal Purple was junk all around and I drained it out within 1000 miles. I've never grinded so many gears in my life as I did with that fluid.
I realize this transmission is not meant for butter smooth or fast shifting, but it seems to be at least acceptable (if not better) when cold (when the fluid is thicker).
Is there any recommendation for an ATF (or something that is compatible) that is maybe on the thicker side than a typical Mercon? I know that gear lube that is typically used in manual transmissions basically destroys the insides of the M5OD.
Whatever fluid I use I seem to have to drain and fill in about 7k-10k intervals as this transmission seems to shear any fluid very quickly. By about 5-6k miles there is a noticeable difference in shift quality from when the fluid was new. So if there is a fluid that should last longer, I'm open to opinions.
Thanks in advance for any help.