I have a 2000 Ford 7.3 4x4 auto transmission with a Suerchips programmer set at hi-perf (+110) a MAC high performance intake system, and a custom built 4" turbo back exhaust. I was told to change out my tranny fluid and use a sythetic to help lower exhaust temp, and was also reccomended to use synthetic oil as well to improve performance and increase engine life. Are these good recomendations? If so, what fluids do you guys recomend? I've heard Royal Purple for the oil, but have no idea about the transmission fluid. Oh yeah, I know the oil is 15 quarts, does anyone know off the top of their how how much tranny fluid I'm going to need.

Thanks Guys!!

 

I would definitely go with a synthetic for the transmission. The jury is still out on the engine. I would at least go with a group three synthetic such as Rotella for the engine. Currently I have a group four synthetic in my engine and I am very happy with it. I do an oil sample in another 2k miles to see how it is performing.
JR

 

HOw often do you change out your transmission fluid? And I will go ahead and go with a group 4. Thanks for the advice so far.

 

I run Mobil Full Snythetic in everything, diff, tranny, t-case, engine. Anything that needs oil gets it.

Synthetics are better. They are engineered for specific applications. Regular oil is made from mineral oil stock which contains contaminants and differend length hydrocarbons. I'm not going to go into the break down of the oils on a molecular level but synthetics last longer, don't break down as easy, pour better, lubricate better and the list goes on.

I've heard good things about Royal Purple. But no fleet runs it around here or up on the North Slope that I know of. They run Rotella and Mobil for the most part.

 

Synthetic is more resistant to heat, especially with the Powerstroke tranny problems. I have a 6spd so I change mine at 60k. The manual says to change autos at 25k, I would change it at 30k or so next one and check out the fluid. My auto transmission fluid has always smelled burnt, so I would start off at normal intervals. If the fluid is a good red and doesn't smell burnt you can try to extend the interval a little longer.
JR

 

Okay...I decided to go with Chevron Delo 400 Oil and Mobil 1 Synthetic ATF. One other question, do you guys go synthetic on the rear end of your trucks?? Thanks Majorpecs!!

 

Majorpecs , I am not a betting man, however if I were, I would be big money that you are running synthetic in the rear diff of your truck.

To answer the question I run synthetic in everything.