GXV Patagonia on the Kenworth K370 chassis

gregmchugh

Observer
So, is that max speed independent of loading or is it relative to loading rates?
Max speed on highway is 65 mph with tire pressure no lower than tire inflation load charts above but max speed would be lower if you reduce tire pressure off highway as shown in the military brochure above, tires still handle the same load at the lower max speeds.
 

Britboaters

Observer
Just to summarize:
- weigh each axle fully loaded
- Refer to the Goodyear published document I posted - note these are industry standard load / pressure tables for 65 mph.
- Use those recommended pressures for best tire performance, if you like.
There are also instructions in the document on the relationship between speed and pressure requirement.
Bob
 
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So, is that max speed independent of loading or is it relative to loading rates?
Some but not the majority of large tires have a dual rating or “singular point”.
For example 18PR Michelin 395/85R20 XZL/XZL+ have a 168G rating (5600kg at 90kph) and also 161J (4750kg at 100kph).
 

gregmchugh

Observer
Just to summarize:
- weigh each axle fully loaded
- Refer to the Goodyear published document I posted - note these are industry standard load / pressure tables for 65 mph.
- Use those recommended pressures for best tire performance, if you like.
There are also instructions in the document on the relationship between speed and pressure requirement.
Bob
Yes, this has been my plan. Thanks for the info I needed for the Goodyear tire load specs.
 

gregmchugh

Observer
Just noticed that the specified max speed for the G278 is 68 mph, not the 65 mph that I mentioned I used as the max speed.
 

beardinc

Observer
I believe our truck with the 18.5 ft body weighed in at right around 21K. Add 1100 lb of water, 1388 lb of diesel and a full stock of recovery equipment, tools and all the things you need I would expect to be around 25-26K max. I've been on some soft sand and on some somewhat rough terrain. Aired down to around 60 psi it did well in moderately loose sand. Keep in mind the tires are designed to operate at 110 psi max. As far as traction goes we had no trouble getting up a fairly loose steep grade in 4wd lo. It has a locking transfer case and I believe it locks front and rear drive axles once engaged. With the locking rear we had plenty of traction. I can see where a front locking diff would be desirable and I'm sure its available but I didn't see the need. I did opt for manual hubs and I think GXV is putting them on all the Kenworth trucks standard now. The first one didn't have them. I'll double check but I really believe the massive divorced transfer case that is going in the Kenworth isn't a "center diff" but a true locking transfer case.

Forgive me if this has already been answered. Any more info on the TC/front drive axel used in this conversion? Make/model would be appreciated.
 

waveslider

Outdoorsman
Not to speak for him - Greg mentioned he might be out of range for a bit but he is a wealth of information and served as a great resource when we were shopping. He also has more miles under his KW platform than many.

Got our kenworth in Feb and its been great.

This weekend.
 

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gregmchugh

Observer
Greg any updates on your truck? I just finished a lengthy visit at GXV and was impressed.
Hi, just got back in cell coverage today. In Palmer AK doing laundry today and heading toward the Yukon and Northwest Territories to do the Dempster Highway up to the Arctic Ocean at Tuktoyaktuk. We were planning to stay in southern Alaska but the smoke from from the wildfire in the Kenai National Wildlife Refuge is pretty bad from Anchorage south so we are heading northeast. Will return to the Kenai peninsula at the last week on July and hopefully the fire will be over by then. We got to Alaska at the beginning of May and spent some time in Fairbanks and Denali NP and then flew down to FL from Anchorage to do some babysitting for our granddaughter and got back up here this week. We plan to return to Denali in late August and roam around until we head south in Oct. Last year it was clear and 60 deg weather at Denali the first week of Oct so we headed there for a few days and then took the Denali Highway across the state and ran into thousands of caribou migrating to the east for the winter. Only got a little snow on the highway between Whitehorse and Dease Lake on the Cassiar Highway last year in Oct so we will se how it goes this year.

The truck is doing fine, we have 38,000 miles on it and spent last summer in Alaska returning in Oct and doing the same thing this year getting to a few places we haven’t been to yet (Top of the World Highway, Dempster, McCarthy, and Valdez). We went up the Dalton Highway last year to the Arctic Circle and may go all the way up to Deadhorse this year. Recently we did a couple of upgrades to the truck, improved front suspension with airbags and another leaf in the spring set and a roof rack on the cab. No major issues with the Kenworth chassis or with the GXV build.
 
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