terrible fuel mileage

**Dennis McInroy** · 07-02-2007, 04:05 PM

I have a 1998 E350 10 passenger van with a 7.3L power stroke diesel, the shop tells me that i have a 3:55:1 gear ration rear end, I`m told the transmission is the only optimum 1 available it is a 3spd with 1 overdrive, we have 16 inch rims overall tire height is 29 inches, we get on the hiway 20mpg in town around 12mpg.
how can we better our fuel mileage (eg: gear ratio, transmission, etc)

**ATCharming** · 07-02-2007, 04:13 PM

holy shit thats a big van!

id say get a smaller gear ratio, but idk how hard itd be to drive that thing since its so heavy...

**Dennis McInroy** · 07-02-2007, 07:24 PM

Originally Posted by ATCharming

holy shit thats a big van!

id say get a smaller gear ratio, but idk how hard itd be to drive that thing since its so heavy...

I have a large family 7 children and the van is not that heavy, overall the weight of the van is only 1758 kg`s or 3800 lbs, compared to most cars that weigh in at over 2500 lbs and only hold 4 passengers, 10 passengers plus driver and only weighs in at 3800 lbs this is not heavy, compared to my semi-truck, and i can drive circles around most cars and their drivers because it is very easy to drive.

now what gear ratio would you suggest that work well with ford vehicles (and yes i have heard the definition of FORD) ? please give me some suggestions.

**ATCharming** · 07-02-2007, 08:20 PM

Originally Posted by Dennis McInroy

I have a large family 7 children and the van is not that heavy, overall the weight of the van is only 1758 kg`s or 3800 lbs, compared to most cars that weigh in at over 2500 lbs and only hold 4 passengers, 10 passengers plus driver and only weighs in at 3800 lbs this is not heavy, compared to my semi-truck, and i can drive circles around most cars and their drivers because it is very easy to drive.

now what gear ratio would you suggest that work well with ford vehicles (and yes i have heard the definition of FORD) ? please give me some suggestions.

3800 is not bad at all for that big of a van. wow

i dont know about ford rear ends, but just something lower would be good. i dont think id go under 3.00 tho, or itd be really slow

**StuntmanMike** · 07-02-2007, 08:24 PM

A cheaper way to lower the gear ratio would be to add a slightly taller tire, if you have the room.

Honestly though, 20mpg sounds pretty good for a vehicle that size. Weight aside, you're basically driving a huge brick down the highway. I have a hard time getting that with my 6 cylinder Grand Cherokee.

Also, you need to weigh the investment with the possible return. If you spend 700 bucks on a gear swap to gain a mpg or two, how long will you have to drive to pay off that gear swap in fuel savings?

Is the van in a good state of tune? Do you drive with a light foot. If you drive a bit slower, say keep it around 60mph on the highway, you should see some savings. All that will cost you is you'll arive at your destination a few minutes later.

I'd check a diesel forum if I were you...there's a lot of guys making big power with PSD's, they have quite a following. I'm sure they could give you some pointers on getting better mileage.

**ATCharming** · 07-02-2007, 08:26 PM

yea hes right about the gear swap... ud have to think about how much ud be benefiting, and how long it'd take to make that money back...

my bad. but yea. 20mpg is real good for that van... im in the teens with my camaro, and its stock.