eou_edu

Ok toyota experts. I don't come around here very often but I hang out on the land cruiser and dodge cummins forums pretty often. As with everybody fuel prices are killing me! I'm considering selling my land cruiser and dodge diesel to put together a mileage king toyota 4runner with a cummins 3.3. I was wondering what is the highest speed rear/front end you can put in a toyota? I know stock they only came with 4.10's, maybe 3.90's in the later years. But is there any aftermarket 3.55's or even 3.07 out there?

I know someone is going to make the bigger tires comment but I'll save you some time. I'm looking for 28 inch tires for the max mileage. Also is there anybody that sells an extra overdrive unit for these like a ranger overdrive or a gear vendor?

nothingbetter

if you want a mileage king, build a pickup, they're lighter

I'm not sure about different gear sets, but I can offer some advice. As we all know power is an issue. So if you gear it down (up?) you'll have absolutly no power...at all. It might make fuel economy worse as you could very well need your foot to the floor to maintain highway speeds. That is of course if your using the 22r/re.

Is this 3.3L the 4bt? If so, you'll be loving life with the gears and fuel economy. But I would reccommend doing the gear and engine swap at the same time. Were you going to just swap the engine or the tranny too? rear end?

eou_edu

I need a mileage king with a few more seats than a pickup can offer. How much does a 4runner weigh anyway? The cummins 3.3 is not the 4bt, that's the 3.9. The 3.3 is about 200 pounds lighter but otherwise fairly similar to the 4bt. They have about 115 horse and 300 lb torque. As I've fairly recently learned from my cummins forum experience the wider the ratio is from horsepower to to torque the lower in the RPM's it peaks out at: Horsepower= torque x rpms/5252. If Plug the numbers to that equation you will find this particular motor peaks at about 2000 rpms. Which of course is a pretty narrow RPM so that means lots of gearing option which I plan to do. But to answer your question it would prefer to go down the road at lower rpm with higher gears. Ideally I want to be turning about 1600 rpms at 60 mph and 2000 rpms at 75 mph. This particular engine would be very happy doing just that. But to complete my quest for gearing I would need a diff ratio a lot higher than 4.10's.

MudHippy

It's funny you should mention it, I was just reading about some 3.07 gears yesterday. And thinking, "damn...that's pretty high gearing". So, I know for sure you can find them for the rear 8". I don't know about the front 7.5". But supposedly there's a 7.5" rear axle with 3.07s too(which would also work in a front 7.5"). I'm unable to verify that they actually exist though.

https://www.yotatech.com/forums/f116...ebuild-209324/

eou_edu

Very interesting. So maybe I just need to take it out of a 2wd. Thank you for that. It will put me in a direction to look anyway.

MudHippy

More specifically:

90 MY 2WD non-Deluxe regular cab, standard bed, 4 speed manual transmission = 3.071 gears(EFI and 5 speed manual transmission = 3.583 gears, EFI and automatic transmission = 3.727 gears, Deluxe = 3.417 gears)

89 MY 2WD non-Deluxe regular cab, standard bed, 4 speed manual transmission = 3.071 gears(Deluxe = 3.417 gears)

88 MY 2WD regular cab, standard bed, automatic transmission = 3.071 gears(w/manual transmission = 3.727 gears)

87 MY 2WD regular cab, standard bed, 4 speed manual transmission = 3.071 gears(other transmissions = 3.727 gears)

85-86 MY 2WD non-SR5, regular cab, standard bed = 3.071 gears(SR5 = 3.583 gears)

To the best of my knowledge...