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How does everyone find their trucks hold up at high speeds? Here all the limits are 60, so curious what the 80 85+ drivers can say for long term wear and tear on the truck
 

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I run 80 on the expressway all the time. I don’t see any extra wear. I just burn more fuel.


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Speed limit for a long stretch of I-10 in west Texas is 80, I have run across there several times in my truck at a little over that, and it's no issue at all.
 

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Most of I-10 through AZ is 75 and trust me, if your going only 75, you’re getting passed like a Yugo on a racetrack!! I regularly run 80-85 (85 is max limit on cruise control. Just FYI) and I have no issues at all.


AZJohnnyO
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I have found some spots in TX that are 85. I hate the fast roads when im towing the camper, 75 is max comfortable for me. I love the 60 roads and get better fuel mpg's.
Other than eating more fuel, mine loves to go fast. Just a 2 door 4+4 tradesman. With the 2 door, I have the 28 gallon fuel tank.
( this being unofficial, of coarse) In northern MN its flat and long stretches of road. I don't know what mine did stock, but burying the needle at 120, and giving it more, the truck takes off, and no wobble, just smoooootthhh.. Ill have to check the cruse setting when back this spring, to see if it cant be set over 85.
 

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I run 82-85 all the time. 'cept with camper/boat 75. It loves to go fast. Maybe this is why I don't get 20 MPG.
 

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My 3500 (with 3.73s) would think I was not feeling well if it didn't get to do 80. Maybe a bit more.
 

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Have done 100MPH in my 3500.

My truck is smooth all the way up and down, but choose your stretch of highway carefully. 8K of truck at that speed does not like anything but flat autobahn type highways. We have lots of smooth roads around me, the run up to Kamloops comes to mind.
 

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Tires would be the obvious fallout from lots of high speed runs.
 

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Tires would be the obvious fallout from lots of high speed runs.
It's not really the amount that counts, but the duration of those runs.

It's heat that kills them, so hours of 100 mph in AZ during the summer is different from shorter bursts of higher speeds, or in cooler weather.
 

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Tires would be the obvious fallout from lots of high speed runs.
The tires on my truck, LT275/70R18 General Grabber HTS60's, have an "S" speed rating, which is 112 MPH, so they will never get close to that on my truck!

I think I might have hit 90 in mine, passing three slow-pokes on a 2-lane highway, and that is the fastest it will ever see.
 

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The tires on my truck, LT275/70R18 General Grabber HTS60's, have an "S" speed rating, which is 112 MPH, so they will never get close to that on my truck!

I think I might have hit 90 in mine, passing three slow-pokes on a 2-lane highway, and that is the fastest it will ever see.

I run Michelin LTX AT2 124/121R LT265/70R18.

100 is really pushing it with an R speed range. I cant imagine front bearings liking those speeds and loads, or the EB when you actually need to slow down. Come to think of it, I have never used the EB to slow from a 100+ MPH run.
 

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Probably shouldn’t post this...

I’ve had this one at ~140. Surprisingly it handled it real good, till I hit a hump in road. Bouncing it a little. With solid axle steering, when front axle compresses, the steering wheel moves. Turns out, at 140, it moves a lot.

I was having fun with a buddy in a 392 challenger. Side by side till 140, he was in shock just as much as me. ( roll at 60).

Anyway, I don’t go over 80 anymore in this HD. The highways around here max at 75MPH.

The steering is not healthy at high speed on these.
 

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I just got back from Michigan. A 1,400 mile one way trip on I 65 and I 75.

80 MPH? You'll get run off the road if that's all you're doing.

But that's about where I stayed. My fuel economy was a hand-calculated 21.7 MPG. Lie-o-meter said 23.4

My truck runs better at 80 than it does at 70.

Seems like there's a little hop to it at lower speeds. Probably the roads.

Each County hires their own contractors to work on the Interstates from what I can gather. So each stretch runs different. Easy to tell how corrupt the County is that you're passing through. They give the jobs to their Brother In Laws or some corrupt Union thugs that will funnel back much of the profits to the corrupt politicians that hired them.

Anyway, in the mountains, driving fast in that thing is no fun. At all. None. On the straights?

WFO. Pedal to the metal
 

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What's with all the folks driving and speeding faster and faster these days? Speeding alin an 8k plus truck is stupid and the OP is ignorant for even asking this question.
 

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What is the highest posted speed limit in your area? There are 2 highways near me posted max is 120KPH/75MPH.
 
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