Two questions

[TheJMan]

1) Have any of you had problems with Arco 87 octane gas in a first-gen explorer? Being thrifty, I decided to buy a tankful because it was cheap and now it seems like my X is pinging and not starting up quickly.

2) How do I tell what kind of differential I have on my 1993 X? I've heard of codes on the doors but what do they mean?

 

[RiverRat]

So it's just the arco 87 or any 87? Post the axle code.

 

[TheJMan]

It's just Arco 87, and according to the sticker on my driver's side doorjamb, the axle code is D4.

 

[Crankcase]

D4= 3.73 Limited slip.

 

[TheJMan]

thank you