What is the best trans fluid to use.

[Snow]

SHO with 100,000 miles on it. Synthetic? Dino? What brand and how much to flush it.

 

[Mr. SHO]

Depends on what year your SHO is. 96-97 require MERCON. 98-99 require MERCON V.

You want a full synthetic ATF. I use Mobil 1 in my '97 b/c Mobil 1 is fine for MERCON designed trannies. If you have a 98-99, you need to find a full synthetic ATF that specifically says it meets MERCON V specifications. AMSOil claims to meet MERCON V, and many have used it in 98-99 trannies with no problems, despite many people saying that it doesn't technically meet the MERCON V spec.

The ATF change procedure is best described HERE

I think it's best to get 4 gallons if you can find the ATF in gallon containers. You will have some left over. I think I used 13 quarts when I last flushed the ATX, and I had enough left to partially flush the PS (about 3/4 quart).

 

[Snow]

Anyone else? What does everyone use?

 

[2 4shofast]

mobil 1 as well :corn:

 

[Mr Anonymous]

Run some Mercon V for about 10 thousand miles, then changeover to a full synthetic. I prefer Amsoil. Mercon V is available at most Ford dealers for $13 per gallon in 1 gallon jugs part number XT-5-GM; so about $52 for a full 16 qt. DIY flush (get an extra gallon if you're going to change the filter).

 

[MilTownSHO]

I just run Dino and make sure to change it regulary. I generally stick to Motorcraft.