How do I figure out which gears I have in my truck? Its an 04 XLT 4.6 4x4 Reg Cab.. Is there somewhere on the truck that will tell me? THanks

Matt

 

I'm looking in the f-150 book and it shows that your truck cam standerd with 3.55's and your options were, 3.73's or 3.75's. I dont know how much that helps you.

 

axle code on door jamb sticker

 

Do a search using "Axle Code" that may help you out more.

 

If you still have the window sticker doesnt that tell you also?

 

Spin them from a stop. If it *kicks out* you have LSD. If it just spins with no motion to the side you have an open diff. Or you can do it the lame way and look at the sticker.

 

LOL I like that idea... So which gears are better? I will have to check the sticker... Thanks guys

 

Alright well I just went and did the lame way of checking and the sticker says 3.55. So what are the advantages to having different gears and which ones are better?

 

im not a mechanic nor an engineer in this stuff but i believe that.. the lower the gear such as a 3.55 compared to a 4.10 mean better gas milage at highway speeds ... however the higher 4.10 gives your engine better mechanical leverage and lets you acellerate faster and pull heavier loads.. however your top speed would be reduced your engine spins faster at highway speeds and waste more fuel.. but the downside to the 3.55 is that its only efficient at highway speeds and lowers the tow rating of the truck..

and F.Y.I the difference between a Limited slip differential and an open diff is that the L/S locks boths tires when enough torque is applied and an open diff tends to send power to the tire with traction