I tow with an 89 3/4 ton Dodge van. It has the 318 with the 999 trans with the low gear set and lock up convertor. Rear gear is a 2.76. I tow an open trailer and the Dart. About the same weight as you.

It tows fine. I towed to Gainesville Fla a few years ago for the division 2 finals with no problems.

I've had the van for 12 years. We used it for a carpet cleaning truck with about 1000 lbs. of equipment in it for 10 years.

The only trouble I've had is a leaky front seal, and the convertor quit locking up. I had the trans rebuilt while it was out to fix the leaky seal and replaced the convertor.

It's a good van. I used it today to tow to Bristol Dragway and I won the King of the Strip 12.00 index class.

Edit: Don't know about fuel usage now. I haven't done the math since the rebuild and new convertor. On the Gainsville trip with the convertor not locking up it got about 13 mpg. It should be better now with the lock up.

Edit again. It does have load helper springs on the rear shocks.