2000 E350 Rear end swap question

Kev in NJ · 05-11-2008, 10:42 AM

I will be buying a 2000 E350 short body passenger van on Monday. It is in great shape at 100K miles and was ordered new for towing so it has the tow package. I will be the second owners. It is a 5.4L V8 4 spd van. It also has a 4.11 limited slip rear and I am a bit concerned about fuel mileage as I will not be towing much with it. Can someone tell me what the expected city/highway mileage would be with the 4.11 rear?

What is the expected mileage for a 3.55 rear?

I am trying to figure out if I would have a payback for changing the rear out so I need the figure how much fuel might cost over time. Keeping in mind we will not be driving this van everyday. We are keeping our cars. I am also making an assumption the rear change is just the rear and speedometer take off gearing, no computer work. What would I expect to pay for a good rear and what is a 4.11 limited slip worth?

We are buying it because it can replace the F250 pick up with it and be able to carry 7 passengers comfortably on trips and still be able to carry various loads. I play with antique cars so I like be able to move stuff. This one has the front bench replaced with buckets and it did not come with the rear bench.
Does anyone know if the rear floor is pre-set with the captured nuts to mount a rear bench if I found one? I already see it has the places for seat belts.

Thanks,

Kevin

Pale Rider · 05-13-2008, 05:55 PM

Kev, I honestly wouldn`t swap that rear out. The trans shift points, ECM, speedo are calibrated for that rear. That Van is heavy, Lowering to 3:55`s will hurt performance and mileage unless you relfash the ecu.
I have the 4.6 with the 3:73 rear in a cargo van and just upgraded to aftermarket 18" wheels with a slightly taller tire and i can definetly notice the difference.
You should be getting anywhere between 13-16 MPG. Even when trying to economize for fuel consumption I doubt it would do better. Remember the van is a flying brick...

no matter what I do my average is between 13.5-15.5
If I`m on a long cruise I can reach 16-17.
But when towing it drops...

I think that 4:11 is exactly what that van needs. it`s actually quicker acceleration which will get you up to speed then kick back and cruise is your best bet for good MPG.

If you want to fine tune, and the engine is in very good running/mechanical condition, then I would think of purchasing a flash tuner and making some adjustments. Good Luck!...