majti
11-14-2008, 04:39 AM
Hi,
i have 6.2d with th400 and 4.625 gears and 33'' tires and my truck is burning fuel as hell. I got 10mpg. I'm hearing that thats too much. Since i hear this is the best mpg engine. Whow much mpg are you guys getting? I've put in new injectors and OH the tranny. What could be wrong?
majti
jvandal
11-14-2008, 07:52 AM
Something sounds wrong... I'm averaging something in the neighborhood of 23-24 MPG... can push that higher on the highway.... lower hot rodding around town.... I've never seen worse than 15MPG...
Does it smoke alot? Oil level staying the same? Oil Blending/thinning?
floriduramax1
11-14-2008, 07:57 AM
Hi,
i have 6.2d with th400 and 4.625 gears and 33'' tires and my truck is burning fuel as hell. I got 10mpg. I'm hearing that thats too much. Since i hear this is the best mpg engine. Whow much mpg are you guys getting? I've put in new injectors and OH the tranny. What could be wrong?
majti
I think you answered your own question...3 speed tranny and 4.62 gears:eek:
majti
11-14-2008, 08:01 AM
Does it smoke alot?
In the morning when i start it..after couple a sec it goes away
Oil level staying the same?
Oil is getting away through rear crank seal :(
majti
majti
11-14-2008, 08:04 AM
I think you answered your own question...3 speed tranny and 4.62 gears:eek:
If i go low as 3.9 (thats the lowes i can go since its a Nissan Patrol truck) what can i expect?
majti
bbbadboy
11-14-2008, 10:29 AM
Should be able to expect 15 mpg with the 3.90 gears, maybe 17 mpg.
jmay2174
11-14-2008, 10:45 AM
The obvious things have already been pointed out. The number 1 change is a 700R4/4L60 automatic transmission with a 0.7 overdrive ratio, a gear splitter, or a 4 speed manual w/OD and a ratio of 0.73. ... 35 inch tires will help a little. Here are some engine rpm's with different configurations at 65 mph:
tranny....rear.....tire.......RPM
output....end.....diam
1.0.........4.625..33........3063 (your current configuration)
0.7.........4.625..33........2145
0.7.........4.625..35........2022
1.0.........3.9.....33........2583
0.7.........3.9.....33........1808
0.7.........3.9.....35........1705
For good millage, you want to cut your rpm's by a third or so, depending on how you drive, whether you tow, etc. Look at the torque curve and you will see there engines really put out the torque at low rpms. See thumbnail on #8:
http://www.dieselplace.com/forum/showthread.php?t=271513