You're an engineer, not a therapist, stop being emotional about mechanical bits that have no feelings whatsoever.
Safe RPM for longer (150 mile), freeway trips
- Thread starter JLANEF
- Start date
Yes. I'm another who's driven 100,000 miles with much of that time on the highway/interstate at 3,000 rpms or better.
Don't worry about it and enjoy the drive.
I had a MGB with no OD and a 1/4-million miles on it, and would right 4250-4750 on the highway for 3 hours straight. I was half expecting a piston to go through the hood but it never happened 
British cars aren't known for longevity, the 4.0 is. It'll be fine. The main issue is sound and comfort suffers and higher RPMs.
As for wear, different parts are affected differently. The valve train is worked harder at higher rpms. Not enough that I'd worry about it.
British cars aren't known for longevity, the 4.0 is. It'll be fine. The main issue is sound and comfort suffers and higher RPMs.
As for wear, different parts are affected differently. The valve train is worked harder at higher rpms. Not enough that I'd worry about it.
OP
Dan,
That was my point exactly, but I appreciate everyone's comments. I'm probably to conservative.
LONGJP2
TJ Expert
Wear ear plugs, and don't look at the tach.
Enjoy the newly found power.
Enjoy the newly found power.
OP
Thanks to everyone. I think the overwhelming consensus is that 3000 to 3200 on the highway should go as far as my butt can handle the seat in a day!! I do appreciate all the comments. Im not going to worry about it!!
3000 rpm isn’t gonna hurt a thing. Maintain the engine with oil changes, new oil filters and air filters and it ll still be running when you ve grown tired of it and want a newer one!
Yes, most will agree with that but it has nothing to do with what actually works and works well. Again, the factory spec is 68 MPH at 3000 RPM at a time when the highway speed limits were faster for extended periods. Since it didn't sink in somehow, that means they knew the vehicle would be driven for long periods of time are RPM levels exceeding 3000. There is a massive difference between cruising at 3000-3300 rpm and bouncing off the rev limiter at 5 grand. One is prudent, one is not safe.
I drive at 60 on the 10 when I am going to and from So Cal as I just cruise and get good gas mileage.
I cruise 60/65 usually. But with my trailer now I do 55/60. For an 8 hour drive it doesn't make a super significant time difference.
65 is when the wind noise gets bad anyway.
Thanks guys for the reassurance on long hauls ,I can set the cruise and get 63 mph and still be right under 3000 rpm,35s 32rh with 4.56
Your speedo is off or your tires are out of whack. 3000 rpm is 68 mph with the 32RH, 35's, and 4.56's.
I checked it with the gps ap next to the speedometer after I installed the 37 tooth speedometer gear,the Mickey Thompson tires are on the short side,do you think that’s the problem.that and I keep it right under 3000
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Your tires are closer to 33". Measure from the ground to the center of the hub and it will be about 16".
A new 35" MTR will measure about 17.25" to the hub center.
I know,I wished they still made the Mtr 35 in 15 inch,the mtz are awesome here in the Missouri mud but we are getting ready to spend a lot of our retirement out west,bummer
my old BMW airhead MC’s have a similar redline as my 4.0. I have, and know many others that do, on a regular basis run 5-6k RPM’s over thousands of miles. I also know many of these MC’s that have in excess of 1/2 a million miles.
I would think running 2/3’s of redline would be a reasonable number… personally I would have no issues running 4k all day. Gas Mileage Be Damned.
It was refreshing to read that 4:10’s and 33’s with the 3speed automatic is a good combination
I would think running 2/3’s of redline would be a reasonable number… personally I would have no issues running 4k all day. Gas Mileage Be Damned.
It was refreshing to read that 4:10’s and 33’s with the 3speed automatic is a good combination
I'm just trying to figure out what Jerry is going to do when his kid takes a job in Minnesota where it gets cold.Out West will be an improvement. Or you could move to FL with @Jerry Bransford.
What kind of gen sets are you guys running? Every one Ive been around in the municipal backup systems typically run at 1800 rpm for 60HZ. Those being Cat,Cummins or Generac's, all diesels of course.