Disappointing fuel economy...

[kim]

"actually with the lock up torque converter the milage difference should be much less...you might want to do a compression test..."

I wasn't aware of that, thanks and will do.

Cheers.

[David*BJ70]

What kind of combo give the better MPG on a BJ70

32" tire with 3.70 (stock gearing)

or

32" tire with 4.11

[Stone]

Originally Posted by David*BJ70

What kind of combo give the better MPG on a BJ70

32" tire with 3.70 (stock gearing)

or

32" tire with 4.11

My guess would be 32" tires with 3.70 gearing.

[brownbear]

Originally Posted by Stone

My guess would be 32" tires with 3.70 gearing.

I agree.

4:11 will give more power, But rev higher and thus burn more fuel. But sometimes if the tire is too big for the gearing the fuel consumption could be improved with better gear. ( to get the engine at the optimum rpm for best fuel burn)

going to low on the rpm is also not good for fuel mileage. But IMOP the 32 with 3:70 gears should be the better of the two....... (not for power)

I have no actual experience with these gears and tires. I run a 32.7 (235/85/r16) with stock 3:70 gears. Before I ran 30's. It seems I get better mileage now. But my speedo is also off now. So I am factoring in a 10% diff. From stock tire diameters.

[lowenbrau]

I'm not sure I agree. I think, with a five speed, you will do better with the 4:11s.
Most of the JDM 70 series have tiny little tires and 4:11s and seem to get good mileage. Its common for a pre '83 BJ60 owner (four speed) to report better mileage than the '83 and later (five speed ) owners. I think you'll get better mileage reving higher with less pedal than reving low with the hammer down.

FWIW I have run 3.7s and 4:88s for long distances in my BJ70 with the same 33" tires. Mileage was similar.

[Gold Boy]

I seem to be doing quite well with 245 75 16's on 4:11's with a auto 4 speed, 100 kph = about 2000 rpm, good economy and not to big for towing.

Small for some, yet they get me everywhere I want to go..

GB

[gedrich]

my old BJ61, 225000km, with a rotary pump 3B used to get 11-12l/100km pretty much all the time. My 12h-t gets 12l/100km so I have noticed much change

[Lantec]

I get about 19 US MPG on 31" tires.

I adjusted the fuel a bit, I've gotten 22 US MPG before but that was when the truck was unbelieveably gutless. From 2nd to 3rd, if there was a slight incline, it would be very sluggish.

At 19 US MPG though, I can go up a steep LONG grade without hitting 1200F on the pyro

[natdog37]

Originally Posted by tlcruiserman

Ok lets get right down to it....


We are all driving really cool Toyota Diesels, so what if they vary on mileage, at least they are not gassers.

Well somebody had to say it

Michael

Dang! just when I thought it was a good thread you went and threw salt in my eyes! I'm getting 10-12 mpg after a tune up.I'll join the club someday though.

[nikalex]

Good Day.
I've posted it before but my 3 or 4 month running average is 10.6 litres per 100 kms or 24.6 mpg (imperial gallon that is) combined driving including stop and go Vancouver commuting.
I had stock 215/80-15's for this period. I thought I was getting poor mileage.
CHeers,
Roman

[Martin White]

Don't forget ODO and SPEEDO don't exactly match. In other words calibrating one by itself with GPS will not necessarily exactly calibrate the ODO. Granted it's not a significant difference, but they are not always a match. I haven't had the opportunity to do this with a large number of HDJ81's (2 total) but in neither did the ODO and SPEEDO exactly match correction factors.

[jmylie]

86 HJ60 with 420K, h55, 33 x 10.50's about 21 MPG US

Always seems to be about the same whether in town or on the highway.

I did try staying around 55 - 60 MPH on the highway to see if MPG would improve, did not make a difference, so back to 65 - 70.

[Glenn-BJ74]

Based on a 2,550 mile average of 70% city and 30% highway, I got 25.85 MPG imperial in my BJ74. GPS corrected mileage on 33X12.5/15 Truxus over July to December 2006, in a 13BT, which was prepped at ATEB in Vancouver.