Are 37's on an 80 to big for an expedition build?

[cody c]

Yeah, I read that the stock R & P gears were good for the 6BT with 35s, and that, IMHO, would be an excellent engine for overlanding. Although, I would run with the rear anti-sway bar, especially with the RTT. That's an awesome roof rack, is it a Prinsu?

Mines a 91 6BT, it limits to 3000 RPM, some of the later ones are made for higher revs. When I first got it, it had 35's and the A440 auto trans and was OK, with the NV4500 it feels like I wouldn't want to be revving much higher at freeway speed. I agree on the anti sway, but it came without it, I should just replace it. I built the rack myself, aluminum rails and steel skeleton, sits no higher than the rubber strips on the roof.

Diesels tend to get excellent mileage when idling, cruising back roads lightly at 40mph with a diesel and you'd see yourself appreciating the swap.

 

[Cruzerman]

One of the (many) reasons I like 35's is that I always air down when overlanding. The ride is so much nicer on rough roads, especially at speed. I find the taller tires give more of a "shock absorber" effect as well as still have decent clearance when some air is taken out.