I have a 2000 F150 4X4 4.6 MANUAL transmission.

It had 60,000 miles on it when I bought it, so I don't know how the transmission was treated during that time. To prevent gear clashing when shifting I have to be VERY ginger with it.

When I got the truck I replaced all fluids as I do when purchasing ANY used vehicle. The transmission lubricant was black. I thought it was dirty, but someone here suggested that maybe someone had put in an additive. It now has nice, clean, fresh ATF as specified by Ford.

I would like to hear from any of you that have FIRST HAND PERSONAL EXPERIENCE with particular manual transmission lubricants or additives that have actually helped the synchronizers to give a smoother shift. I'm not looking for someone to push their favorite concoction, but I am looking for FIRST HAND PERSONAL EXPERIENCE with lubricants or additives that have ACUTALLY SHOWN an improvement.

Thanks for any responses that you might offer.

Have a great day,
Doc

 

i believe the shifting is a function of the porr quality of the transmission design, not any oil or addative to the oil. Personally, i have not heard of an "addative" for regular manual transmissions. The MERCON is about the best oil you can buy.

 

I have never heard of an additive either. I think that may have either been the original fluid or the wrong fluid. I change out the fluid in my m5OD every 20,000 - 30,000 miles depending on how lazy I am and it always comes out red like when it went in.

 

My 5-speed gears clash sometimes too if I am not careful while shifting. It was noted on the Buyers guide when I purchased the vehicle... but could not understand what was meant by it. Now that I see other users on here talking about the same "Clashing" what is meant of it? Is it just the sycnrhonizers in the M5OD being designed poorly causing an indefinite amount of clash no matter what? I have 113,000 miles on my 4.6L w/ 5-speed. Performance wise it doesn't seem to be affecting my shifting or the power of th emotor.
Do you think changing the Manual fluid will help at all? Also, how do I go about flushing the manual transmission fluid? Never had to do it on a truck, is it any different than let's say a 5-speed Honda?

 

The first change on my M5OD the fluid came out black. When i had a sample tested it came back as Gear Oil, not ATF. I think that the original owner was told that manual trans take gear oil, not ATF. If you keep the fluid changeed every 20 - 30K you will notice a lot less clash.

I put in MERCON ATF, no additaves or any thing else and i have nearly 155K on this trans.

 

Those M5OD do not like additives(thickeners mostly) they have a small fluid guide that provide the lubrication for the gears, if you give that a good cleaning every so often your tranny will see many more miles.

 

So I simply go to my local AutoZone and pick up a gallon of Mercon V and flush the fluid? the M5OD uses ATF right, just verifying with the posts I read here.

Also, how do I get the old stuff out and the new stuff in?

Thanks,
-Tom

 

You want straight Mercon ATF not Mercon V. There is a difference in formula apperently.

There are two plugs on the trany. One to fill and one to drain. The easest way to fill is to pull the stick out and fill it where the stck enters the trany.