Possible new class 5 rig. Am I nut's to choose gas motor ?

[86scotty]

High idle diesel and DC-DC might negate that generator need. Plus you'll have room for lots of lithium for overnight AC (etc). Might solve your dual fuel issues.

Please don't camp near me if you're going to idle a diesel to charge batteries. Even a new quiet one with a stock exhaust.

I speak for everyone in the world I'm pretty sure.

 

[ExpoMike]

But in some of the more remote areas I wonder if diesel would be harder to find?

I ran into this in Death Valley. The group was near Stovepipe Wells and I was the only diesel in the group. They didn't sell diesel there so we all had to drive to Furnace Creek, for me. Was really low by then.

My '97 Ram was a 12v Cummins but when I bought my current 2000 Ram, I went with an 8.0L V10 gas. So much simpler to deal with but does get about 9mpg 😕

 

[driveby]

I'm with you 100%. I hate generators and certainly idling anything. I plan to "over battery" if that's a word and the high idle would be under duress as a last resort. Lots of solar on the roof and plenty of amp hours hopefully means I'll never actually need to high ilde (or genny for that matter).

 

[klahanie]

TL;DR - skip the generator, get more batteries.

You haven’t shared your budget (you don’t need too, necessarily) but with the cost of lithium ion batteries coming down and the space that will be available to you on a 550/5500 platform, I can’t think of any reason why you’d want to get a generator over additional storage capacity.

I can imagine if your use case involves lots of winter camping at high latitudes while using the minisplit to provide heat that battery capacity can be a concern. In that case, a generator may provide some peace of mind. Likewise, depending upon the battery system, AC, and washer/dryer you’re considering, you may run into issues of max current draw outstripping the battery BMS’s ability to flow that amount of current, but this can be planned for in advance and is most likely just theoretical.

Sounds like it is going to be a cool project.

Hey Andy,

Yeah 5-8kw of storage is doable ($), it's the filling up them up that is the trick. Massive solar systems are key components for some, not sure it will be for me.
As for budget numbers, preliminary estimating has already exceeded my target. But for fun let's say, worst case and all in, 200K USD. portioned as: 75K truck & new wheels, 100K shell box and subframe/deck etc, 25K box build out, 0K for personal labour.

You might see right there that's going to require some "value" choices having to be made. And we may decide to go back to the turnkey retail PU+camper model solution.

btw you have a mini split, yes ? how is the dust/dirt situation on the external part (rear wall). Do you ever use a cover over it while driving ?

 

[klahanie]

Please don't camp near me if you're going to idle a diesel to charge batteries. Even a new quiet one with a stock exhaust.

I speak for everyone in the world I'm pretty sure.

Be nice if that could be extended to shouting, yelling, general 'ell raising, midnight troubadours, loud music, loud mouths etc, etc. We've been subject to all of that and more at all hours. Multiple times.

You gotta love people

 

[86scotty]

Be nice if that could be extended to shouting, yelling, general 'ell raising, midnight troubadours, loud music, loud mouths etc, etc. We've been subject to all of that and more at all hours. Multiple times.

You gotta love people

I agree, which is why I would prioritize fitting out a rig which will get you further than most care to go. I just did this over the week of July 4th. We could only fit a trip in then and knew it was a risk. Headed to the Colorado high country expecting to fight for even remote spots and found 5 of them, none of which would've been accessible with a 2wd.

 

[andy_b]

Hey Andy,

Yeah 5-8kw of storage is doable ($), it's the filling up them up that is the trick. Massive solar systems are key components for some, not sure it will be for me.
As for budget numbers, preliminary estimating has already exceeded my target. But for fun let's say, worst case and all in, 200K USD. portioned as: 75K truck & new wheels, 100K shell box and subframe/deck etc, 25K box build out, 0K for personal labour.

You might see right there that's going to require some "value" choices having to be made. And we may decide to go back to the turnkey retail PU+camper model solution.

btw you have a mini split, yes ? how is the dust/dirt situation on the external part (rear wall). Do you ever use a cover over it while driving ?

Our minisplit has been fine, dust/dirt wise. It sits high up on the rear wall so it gets dirty but not terrible. Never considered covering it - too lazy.

Our total costs were similar although the camper body and build out costs were reversed; labor (labour!) costs were the same.

We have 7200kwh of storage; our 800w of solar (~600w maximal efficiency in the summer in the desert) keeps our system topped off during the the day and recharges it in a few hours the next day despite continuous AC use in summer. We never use the DC-DC converter in the summer.

In the winter, we have to rely more on our DC-DC converter which currently an older Victron Orion. It gets super hot and throttles down from 30a to mid-20s pretty quickly. The newer Orion XS should be better (higher efficiency (50a) and better thermal management, allegedly). Even with limited sun in the winter, we haven’t had much trouble although this is in the lower latitudes and without heavy snow. There are other DC-DC converters with even higher output but I wanted to stay with Victron for ease of monitoring. I know I could wire more than one together but, again, no need for our use case.

 

[McCarthy]

Gearing is a huge part of building a truck with a 7.3. The difference between 3.73's and 4.30's is massive when running big tires, with big wind sails (campers or trailers) behind them. If you have a 3.73 truck with 37's or larger look at 4.56's- biggest difference one can make without power adders.

 

[klahanie]

Gearing is a huge part of building a truck with a 7.3. The difference between 3.73's and 4.30's is massive when running big tires, with big wind sails (campers or trailers) behind them. If you have a 3.73 truck with 37's or larger look at 4.56's- biggest difference one can make without power adders.

The F4/550s chassis are avail with 4.88 which is what I'd choose. Not much diff over 4.56 but it's something. Prob will drive hwy speed slowish to help with fuel anyway (65mph max)

I'm leaning towards the 7.3 mainly for the cheaper initial cost. Going to find out soon when the order bank switch over to 2025s is expected then hopefully make my engine choice

 

[WOODY2]

I ran into this in Death Valley. The group was near Stovepipe Wells and I was the only diesel in the group. They didn't sell diesel there so we all had to drive to Furnace Creek, for me. Was really low by then.

My '97 Ram was a 12v Cummins but when I bought my current 2000 Ram, I went with an 8.0L V10 gas. So much simpler to deal with but does get about 9mpg 😕

Almost better to escape to Beatty?

 

[andy_b]

The F4/550s chassis are avail with 4.88 which is what I'd choose. Not much diff over 4.56 but it's something. Prob will drive hwy speed slowish to help with fuel anyway (65mph max)

I'm leaning towards the 7.3 mainly for the cheaper initial cost. Going to find out soon when the order bank switch over to 2025s is expected then hopefully make my engine choice

Long McArthur Ford does a great weekly update of Ford’s production capacity for all of their various models. According to their most recent update (week of 7/8), the order banks for regular Super Duties (not 450/550) are still open. I’ve been watching them a bit this past year and it seems like 450s are rarer than hen’s teeth; they have never commented on 550s.

No relationship w/ these guys; sharing only because it seems like a handy thing to know if you’re considering ordering a Ford Super Duty.

To answer the original question of this thread: I’d get the 7.3L. I agree that the 6.7L has tremendous chooch and would be fun to have crossing mountain passes, etc. However, I think diesel is gross. Fueling it, dealing with DEF and associated emission controls, diesel fumes at slow trail speeds are all things I would want to avoid. Modern diesels are way cleaner and quieter than my old 7.3 but as a $13,000 option, the HO 6.7L (I mean, if you’re going to get one, get the good one) just doesn’t have enough value to justify it to me. This opinion is worth that you paid for it.

 

[rruff]

Gearing is a huge part of building a truck with a 7.3. The difference between 3.73's and 4.30's is massive when running big tires, with big wind sails (campers or trailers) behind them. If you have a 3.73 truck with 37's or larger look at 4.56's- biggest difference one can make without power adders.

I agree that getting the lowest factory gearing is worth it, but...

I'm skeptical of the "massive" part. You're basically just effecting 1st gear... which will make a noticeable difference off the line with a big ratio change. Won't help you get over the pass though.

If the Ford SDs are programmed anything like my truck, a throttle mapping device or just turning on tow/haul mode can make a huge difference.

 

[mog]

or just turning on tow/haul mode can make a huge difference.

I have a Kodiak C4500 (8.1 gas) that has 5.13 factory gears on 42s. Around town and getting on the highway I just have the electronic overdrive (5th-Allison 1000) switched off and it drives 'normal'. Once at cruising speed, I switch the overdrive on. Easy as falling off a running board.

 

[PDX_Jay]

I've got the 7.3 in my F250 - flatbed and camper, total weight is around 10k (not finished with the build yet, but will be soon and will get actual weight). Last 1,000 miles or so I've averaged 11.3 mpg. I drive pretty conservatively, and that's no real off-roading... just forest roads. Been very happy with the choice to go with the gas engine. I also have the transfer flow 58 gallon tank - so range is 500-600 miles, which is more than adequate for me.

 

[McCarthy]

I agree that getting the lowest factory gearing is worth it, but...

I'm skeptical of the "massive" part. You're basically just effecting 1st gear... which will make a noticeable difference off the line with a big ratio change. Won't help you get over the pass though.

If the Ford SDs are programmed anything like my truck, a throttle mapping device or just turning on tow/haul mode can make a huge difference.

No you're most certainly not affecting just first gear. Wow.

If a 3.73 truck turns 1900rpm at 75mph, a 4.30 truck would turn approx 2200 rpm. Massive difference. Same goes for every gear.

That's why it's called a final drive. It affects the final drive of each gear, as well as acting as a torque multiplier.