Help me Decide...

[kustomizingkid]

I'm using this great site and knowledge to help me narrow down my full fluid selections for my car. So I am trying to narrow down my fluid selections for the rest of my car. The car in question is a 98 Lincoln Mark VIII, 4r70w, 8.8.

I'm thinking of using Motorcraft Mercron V. I have no clue on the diff fluid, thinking of going synthetic. As far as brake fluid and power steering fluid I also have no opinion.

I'd love to hear any suggestions.

 

[Falcon_LS]

Motorcraft High Performance DOT 3 is a brilliant choice as far as brake fluid is concerned, and so is Motorcraft Premium Rear Axle Lubricant 80W-90 for your differential. If you want synthetic differential fluid, Amsoil is a good option.

That said, I know many who use Mercon V in their 4R70W with no problems.

 

[bdcardinal]

Motorcraft Mercon V in the trans and power steering.

XY-75W140-QL with a bottle of XL-3 friction modifier in the rear.

Motorcraft brake fluid, PM-1C is a good choice. i personally use either the Valvoline or Castrol brake fluid just because its inexpensive and i can get it in quart bottles.

 

[Falcon_LS]

Isn't 75W-140 too thick? I thought that was a heavy-duty axle lubricant.

 

[vregan]

I've had excellent success with Redline Gear Oil (check what weight is spec'd for your specific car) and Valvoline Synpower Brake fluid in my '89 Vette. The VSBF lasts a LONG time without showing effects of moisture in the master cylinder!

 

[c3po]

Originally Posted By: Falcon_LS
Isn't 75W-140 too thick? I thought that was a heavy-duty axle lubricant.

My 2004 Mercury Marauder's Differential is speced for 75W-140.

I think they went to that weight because they were having some problems with the thinner gear weight oil.

 

[Falcon_LS]

Not sure about Marauders, but I know my Grand Marquis used 80W-90. Suppose it varies by application.

 

[bdcardinal]

Police Interceptors have 75W140 from the factory. I would use it in the Mark being that it is an IRS.

We have actually been told to use 75W140 in all diff's being serviced.

 

[kustomizingkid]

I should mention that I am running 4.30 gears and a Ford Tlock in my rear end vs the factory open diff and 3.27 gears. The rear end is the one place I wouldn't mind running a more expensive synthetic if there is an advantage to it, same with the power steering, mainly due to the much monger change intervals.