[slowmover]

I plan on hooking up both the oil pan heaters and the coolant heater to the same timered power strip--that way I only have one thing to plug in.

There are some discussions about oil sump heaters on BITOG and the recommendation is to make sure the oil temp (in-sump) does not exceed 150F as one will start to cook the oil. (Yes, I realize that 260-270F is often cited for oil temp max on a running engine. The concern here is that the heaters create hot spots without pump circulation; bad chemistry starts to form IIRC). The happy curve is short. An email to Cummins wouldn't hurt to help clarify this.

I'd be inclined to use them on the trans and differential as you've noted, but with electrical outlets (perhaps [2] separate 20A type) and cabling built to withstand the amperage draw. GFCI's are not happy with this sort of set-up I'm told.

It would be worth some planning as well to determine actual in-sump temperatures, not just IR gun readings of the pans/cases exterior.

So far I haven't noticed any unusual tread wear. I probably should take another close look to make sure.

A tread depth gauge is about $5 at NAPA. I trend the treadwear at 20k mile intervals (of which there are from 5-7 on the OEM Michelin tires when driven for long life).

80 psi max sidewall seemed like a lot to me when I first looked at it as well, but I guess I just have "stronger" tires. My wife has 17-inch tires on her Blazer and her max sidewall is only 35 psi. I guess it just depends on the tire.

The 3/4 & 1T trucks use a Load Range E tire capable of supporting in excess of 3,000-lbs each at full pressure. Matching load to pressure brings best results (plus maybe an increase of 10-15% to help stiffen the sidewalls, IMO). My truck -- identical in most respects -- calls for the LR-E tires to be run at 50FF/50RR when solo, and 50FF/70RR when fully loaded. My repeated highs of 27 mpg were achieved at the 50/50 pressures. I have moved to 60FF and 50RR to help with any potential "scrub" in turns on the front. (My first set went 120k with 4/32's remaining; this first replacement set may make take the truck to 250k).

The wifes Blazer is using a P designation tire for soft ride. If you ever want to set it up for better highway/towing stability, then an LT [Light Truck] tire -- as recommended by Michelin or other -- would be best. This might also help with FE somewhat.

Thanks for the update. Sooner rather than later I hope to make a start on some mods for my truck.

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