Normal RPM's

[kylant]

What are the normal RPM's at 65 mph for a bone stock Dura/Allison combo?

How about 70, 75, etc...?

I noticed I was about 2,000 at 65 mph. This seems high to me, I seem to remeber being lower with my 8.1L big block, Allison, and 4.10 gears.

I thought diesels ran at much lower RMP's!?

Is this normal or is my tranny not going into overdrive? It seems to be though :confused:

thanks

[redrider#1]

It would depend somewhat on your tire size and load as well, but is seems that I run around 2200 at 75mph unloaded with 235/85/R16's which are a litte taller than stock(overall gearing would be a little higher). I expected the rpm's to be lower as well, but this seems to be close to what you are getting.

[BlackMax 2001]

I have a bone stock 2001 D/A. At 65 mph, my rpm's are around 2000. At 70 mph, it's around 2100, and at 75 mph ( and i run here a lot) it runs around 2250 rpm's. You sound ok to me. Keep driving and grinning. :cool:

[rdlit]

I run about 2000 rpm @65 and 2250 @ 75 also, however, you may not be running these exact speeds. When i checked my speedo with the stock tires, It was off about 4 mph @ 75. However, your rpm does seem about right for 3.73 gear.

[Driveshaft]

Somebody's off, mine runs approx 2050 rpm's at 70 mph, 65 mph = 1800ish, 55 mph = 1450 or so, 75 is somewhere around 2225 or 2250 best I remember.

[JD Diesel]

Driveshaft thats about where mine runs at. JD :D