'03 XLT/FX4 Level 1 diff questions
 

I haven't been able to find a clear answer on this but since my truck is an '03 4x4 with the FX4 Level 1 package on it, does it take 80w-90 fluid or 75w-140 fluid? Seeing as how the level one is basicly the same as a regular XLT 4x4 I'm not sure. Would like to change it out soon, want to make sure I get the correct fluid.

Also, I would assume this truck has the 4:10 limited slip...is it also limited slip in the front or just open?

Not real clear about what exactly the fx4 L1, L2, and regular XLT 4x4 differences were in '03.

look in your owners manual...it will tell you what to use

80w-90 with a friction modifier, and the front dif is open. The level 2 had 31 spline axles and torsen limited slip.

Thats kinda what I figured. Same as regular 4x4

I did but not sure which fluid I should used based on the differences due to level 1 vs level 2

do you tow? play offroad much? go with the 80w-90 ( if you ever play in the water run synthetic or just change it out after you get wet...) I run a 80w90 synthetic blend in my Jeep with the ARB's and change out anytime I go swimming just incase...

My trucks running whatever ford put in it ( only been changed somewhere around mile 6000) 130,000 something miles ago.... Same as the tranny...

Tow a few times a year, play offroad or go swimming? Nah...just an occassional romp around a field.

what spline count is the diff in the fx4 off-road

i think their 28 spline axles

Can you tell me what gear ratio mine would have? I would assume 4.10

yea because you have an fx4 id say your axle code is R7 which means you have an 8.8 4.10 LS rear axle

no not the same the regular 4x4 has axle code 97 which is an 8.8 4.10 open rear axle...i feel like shane now lol