What would be a safe/comfortable cruise rpm in the 55-60 MPH range with a 6.2? Is 2600-2800 too hard to run it for a short time (250 miles) for one trip? Will be used around town after that, then regeared with bigger tires.
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Whats your rpm with a 6.2?
- Thread starter ryan22re
- Start date
FWP
CRS
Shiat no. I think Rene went from Canada to Moab and back at that RPM 
JeffHK5
1/2 ton status
My 84 dump/tow rig has a th400/4.10/29.5 tire and using the speed to rpm calc. that I got here, my rpms are around 2,900 at 65 mph. I was told by a couple guys on a diesel forum I frequent that 3,000 rpm is a good max rpm for any long periods of time. I believe the 6.2 has a 3,250 red-line and overheating is a common problem when there run that hard. I can tell you that my 6.2 has 80K on it and it sounds like it's guts are coming out the tailpipe above 65mph!
Jeff
Jeff
FWP said:Shiat no. I think Rene went from Canada to Moab and back at that RPM
Yup, 2600 rpm on the highway...1200 miles each way. It got on my nerves listening to it, but the truck seemed to like it just fine.
They're governed to 3600 rpm FWIW.
Rene
JeffHK5 said:
i thought it didn't have a red-line simply because of the govern which rene mentioned.
JeffHK5
1/2 ton status
I have a speedo but no tach , I was told they have a visual red-line on the tach at 3,200. I have not seen one firsthand so my statement should have had a "?" behind it.
I have ran my truck at 2,900 (68 mph) for over 3 hours with no problems.
Jeff
I have ran my truck at 2,900 (68 mph) for over 3 hours with no problems.
Jeff
M1008 (one ton) CUCVs have 4.56 and a 29" tire. The wind up pretty tight at 65mph 
. Pushed for a long distance at high RPM they have a tendency to blow front and/or rear main seals.
Oh ya, HMMWVs have 3.08 diff plus a geared hub ratio of 1.92 (on a 36-37" tire). "MAXIMUM RECOMENDED SPEED OF 55 MPH" (unless you're being shot at). Thank god they went to the 4L80E for the A2 models
. Pushed for a long distance at high RPM they have a tendency to blow front and/or rear main seals. Oh ya, HMMWVs have 3.08 diff plus a geared hub ratio of 1.92 (on a 36-37" tire). "MAXIMUM RECOMENDED SPEED OF 55 MPH" (unless you're being shot at). Thank god they went to the 4L80E for the A2 models
DieselDan said:M1008 (one ton) CUCVs have 4.56 and a 29" tire. The wind up pretty tight at 65mph
Oh ya, HMMWVs have 3.08 diff plus a geared hub ratio of 1.92 (on a 36-37" tire). "MAXIMUM RECOMENDED SPEED OF 55 MPH" (unless you're being shot at). Thank god they went to the 4L80E for the A2 models
A friend of mine had a dually crew cab 2wd with 4.56 gears and he lowered it and put lower profile tires, and he used to push 3300 RPM going 600-800 mile trips for a couple of years, he had the tiny tach to confirm the RPM's.
He ended up blowing the main seal but he fixed that and siwtched to 3.73 gears now.
but the engine still runs strong. It sucked fuel though like you wouldn't believe at 3300 RPM all the time
