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Old 08-08-2019, 04:56 PM   #31
kognito
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And I know I said it much earlier in this thread, but I still can't believe how much better my 1500 rides with 4 psi less in each tire than GM "recommends"

GM's recommended psi is for max load, I rarely carry much weight. When I am getting a load of top soil or mulch I just pump them up.

Plus I like how it annoys Onstar that thinks my air pressure is low
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Old 08-08-2019, 05:03 PM   #32
Nick M3
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Quote:
Originally Posted by kognito View Post
And I know I said it much earlier in this thread, but I still can't believe how much better my 1500 rides with 4 psi less in each tire than GM "recommends"

GM's recommended psi is for max load, I rarely carry much weight. When I am getting a load of top soil or mulch I just pump them up.

Plus I like how it annoys Onstar that thinks my air pressure is low
LOL. I run 30 psi under the recommended rear pressure in my HD. I figure that the front axle carries 4,000lbs. on 50psi, so the rear can carry the 3,000lbs. empty weight on 50 as well. (Recommend pressure is 80!)

Tire wear is WAY better this way, too.
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Old 08-08-2019, 05:48 PM   #33
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Quote:
Originally Posted by Nick M3 View Post
LOL. I run 30 psi under the recommended rear pressure in my HD. I figure that the front axle carries 4,000lbs. on 50psi, so the rear can carry the 3,000lbs. empty weight on 50 as well. (Recommend pressure is 80!)
Wait, what? 80 PSI?

Colorado's recommended is 35. I'm running 34/33.

I can try 30 At what point to 255/65R17 truck tires start to get weird?

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Have you considered putting 500lbs. in the bed?
Doesn't that require me to remove 500 lbs of stuff every time I want to use it as a truck?

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How are the secondary oscillations?
With the stock shocks it can get a bit out of control. With the Fox shocks, handled very well.
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Old 08-08-2019, 07:57 PM   #34
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Quote:
Originally Posted by Nick M3 View Post
LOL. I run 30 psi under the recommended rear pressure in my HD. I figure that the front axle carries 4,000lbs. on 50psi, so the rear can carry the 3,000lbs. empty weight on 50 as well. (Recommend pressure is 80!)

Tire wear is WAY better this way, too.
And your Duramax weighs what, about half of my 5.7 V8?

My F550 had air suspension on the rear axle, I didn't want to mess with air pressure on the dually tires, so I mounted a second limit switch on the suspension so I could run different air pressure on the air bags between loaded and unloaded. My 5th wheel pin weight was about 5600 pounds! Truck drove so smooth when loaded, but until I added the second switch it sucked driving the truck after unhooking the 5th wheel.
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Old 08-09-2019, 10:10 AM   #35
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Wait, what? 80 PSI?

Colorado's recommended is 35. I'm running 34/33.

I can try 30 At what point to 255/65R17 truck tires start to get weird?


Doesn't that require me to remove 500 lbs of stuff every time I want to use it as a truck?


With the stock shocks it can get a bit out of control. With the Fox shocks, handled very well.
I mean, it depends on what you want to use it as a truck for. If you're running into load limits, then yes. If it's a space issue, than a big piece of steel plate will weigh it down without impacting available volume.

But mostly, I was thinking that you'd try it for starters and see. You know, throw a couple sets of wheels in the back and see if it rides better.

And yes, the specified rear tire pressure for my truck is 80 pounds per square inch. With 50 up front, which makes that easy. If they are running identical pressures front and rear, you aren't going to have the opportunity to do much.

I'll also note that the Michelin all season tires ride a lot better than the Bridgestones it came with, or the Bridgestone A/T tires I was talked into putting on (and regretted).
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Old 08-09-2019, 01:19 PM   #36
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I air down the ram rear tires in the winter but in the spring they live at 80, which is the common max load inflation pressure for a load range E tire.

It does ride better with the rear at 60psi.

For a mid size truck if be hesitant to go lower than the recommended pressures. The side walls on those tires are generally super weak.
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