Alright guys, I've been gone from the site for a while (busy time in my life, including gettin' hitched!). The time has come for a tranny fluid change, what is the best fluid to use (Amsoil not included)? I was generally looking for a synthetic, but I'm having a hard time finding a sythetic Mercon V. Thanks for y'all's help!

 

I couldn't find any 100% synthetic in the local parts stores.

Used Castrol Mercon V which is "part-synthetic". The tranny pan gasket is reusable so you won't need the cheap cork gasket that comes in the filter kit. I paid $64cdn for 13 quarts of the Castrol.

 

HI!... REDLINE!!!!!!! I've been running this in my tranny and rearend for 3 years now with NO problems.

 

wemjr,

Do you have the 4R70W or the 4R100 behind your 5.4L?

The '98 on 4R70W needs Mercon V whereas the '97 can use regular Mercon.

Also: The 4R100 uses Mercon not Mercon V.

I'd recommend Redline for the 4R100 as well but they don't make any specific reference to meeting Mercon V requirements so I don't think the '98 on 4R70W is covered.

 

Does Mobil 1 ATF meet these requirements?

 

Mobil 1 has a MERCON, not MERCON V rating.

Mark

 

I have the 4R70W tranny. If I can't find a Mercon V full synthetic, what is the next best thing and where is the best place to get it? Most of the stores around here hardly carry any fluid let alone synthetic.

 

AMSOIL. E-mail me and I'll be glad to help you out.