The electric GMC fully imagined -

I have participated in lots of meandering conversations on this so I thought i would put all my silly thoughts in one place.

I think a 300-400 mi range electric GMC is totally doable.

Some of these numbers are just guesses so feel free to challenge them.

A Tesla S weighs 4200 lb with a 1200 lb battery. A GMC weighs around 11,000 lb give or take.


The engine, transmission, exhaust, cooling, tanks, generator and fluids weighs over 2300 lb.

One Tesla motor only weighs 110 lb. So, by my guess, two motors and three batteries would only add 1700lb net after you removed all the ICE stuff.

The drag coefficient of a GMC with a clean roof is .30 - the Tesla S is .24


To do this today would be at least $60,000 in used parts but in a few years when there are a pile of EV parts in junkyards the math is there and the GMC is an excellent candidate.

I used Tesla because the numbers are readily available but Amazon ordered 100,000 Rivian electric trucks. That will also contribute the parts supply.
 
I have participated in lots of meandering conversations on this so I thought i would put all my silly thoughts in one place.

I think a 300-400 mi range electric GMC is totally doable.

Some of these numbers are just guesses so feel free to challenge them.

A Tesla S weighs 4200 lb with a 1200 lb battery. A GMC weighs around 11,000 lb give or take.


The engine, transmission, exhaust, cooling, tanks, generator and fluids weighs over 2300 lb.

One Tesla motor only weighs 110 lb. So, by my guess, two motors and three batteries would only add 1700lb net after you removed all the ICE stuff.

The drag coefficient of a GMC with a clean roof is .30 - the Tesla S is .24


To do this today would be at least $60,000 in used parts but in a few years when there are a pile of EV parts in junkyards the math is there and the GMC is an excellent candidate.

I used Tesla because the numbers are readily available but Amazon ordered 100,000 Rivian electric trucks. That will also contribute the parts supply.
Electric cars may be at the point where they can do short hops but the technology is not even there for trucks. They have severe limitations when trying to travel. Here in Arizona there is a article where people tried to drive between Phoenix and Flagstaff and with the steep grade, bumper to bumper trafic it took them three days to drive what should have been a few hours.

Of cours in a RV this even gets worse because of all the weight. The new Ford Truck weighs nearly twice as much as its counterpart because of the motor and batteries. Personally I cant see myself driving a 24,000 pound RV down the road even if you could get it licensed and insured for that weight. What about Brakes!!!!!!!!!

Currently, I am not aware of any state parks with charging stations, which brings up the charging problem. It would take a wall outlet at least 30hrs to charge enough batteries to tug all that weight.

 
electric is kool, fancy and efficient,
Maybe to some people in a local/commuter sense. My pal in Calgary bought a Tesla. It takes him hours more than before to run down to Vancouver because he has to stop to charge up. Not sure how efficient that is.
 
Maybe to some people in a local/commuter sense. My pal in Calgary bought a Tesla. It takes him hours more than before to run down to Vancouver because he has to stop to charge up. Not sure how efficient that is.

I've heard the same from friends traveling in all electric tiny cars, nissan leaf and tesla.

The tesla owners were able to successfully do long trips, carefully planning their route and charging stops. They didn't complain about any inconvenience but I'm not sure they would anyway and I'm sure it wouldn't work for me. I'm not ok sitting around for an hour while the battery charges. The Leaf owner was doing good until one of the charge points he planned on using went down for maintenance _after_ he left his house. Luckily there was a charge station at a nearby Nissan dealer that he was able to use. Just lucky though. And he spent a lot of time on that relatively short trip, just charging or looking for a charger. Seems very stressful to me.

And these are tiny vehicles trying to go cross country. Imagine in a 12k lb RV. Diesel over electric would be ideal. Charge when you can or it's convenient, drive efficiently with diesel the rest of the time.
 
This is all interesting on a EV GMC. Heavy vehicles just don’t seem to do well in EV, and I imagine RV’s have even more of a challenge when hopping around in the mountains. I am curious on Toyota’s more robust effort in hydrogen engine development, what I read its a better application for large vehicles. The challenges now are the higher cost of hydrogen and the lack of available fill sources. One solution for the availability is do multiple fuel cell module replacement units, where as hydrogen production would be more centralized and the storage and distribution of hydrogen replacement cells would be trucked to a filling station. Not sure if this distribution makes sense or just simply constructing large storage at the the filling stations of hydrogen is even possible? Just don’t know enough about its dangers and stability. Anyhow, for sure a ways out.

TG
 
Still working through the Mach E swap. It runs well, but I haven’t taken it over 15MPH because my driveshafts are makeshift at this point. I pretty much drive it every couple days from an RV lot to my house, do some work and drive it back. Not sure what the range will be when I actually take it on the open highway….maybe 120miles? I’ve got some estimates to have the driveshafts machined…..the whole project is a lot of fun, but I can only work on it so much because of my day job and monthly budget….
 
Some build custom vehicles just because they want to! There doesn't have to be any reason or justification or return on investment.

My Bolt has a 65Kwh battery (250mi range or 3.8mi/kw)) and I can charge at home 115V/230V 15A (1.7Kw/h/3.4kw/h) with the supplied charger. A DC fast charger can charge at about 54Kwh as long as SOC is below 60%, then the BMS regulates the charge rate.

My guess is a GMC EV could get close to 3.5mi/kw on flat ground, uphill and the weight is an issue. The regenerative charging going downhill needs to be maximized.
If I were to build one, I might consider a deeper aluminum frame and lightweight composite insulated floor for weight reduction and more room for batteries.
 
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Using the Tesla X as a example and Just doing a little math. Our motorhomes already weigh 12, 000 lbs. To get about the same distance the Tesla gets you would need 4 battery packs bringing the weight up to 17,508 lbs.

Oh but then you would need to add a lot of steel to reinforces the frame, redesign the suspension, and do a completer re-engeering of the brake system (semi truck brakes?). So you will need a fifth 1377 lb battery, maybe a sixth, larger motor ect. Then still you will need a larger generator to charge the batteries since there are no charging stations with that kind of capacity. Could be done if you were the winner of the last big lottery.
 
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Using the Tesla X as a example and Just doing a little math. Our motorhomes already weigh 12, 000 lbs. To get about the same distance the Tesla gets you would need 4 battery packs bringing the weight up to 17,508 lbs.

Oh but then you would need to add a lot of steel to reinforces the frame, redesign the suspension, and do a completer re-engeering of the brake system (semi truck brakes?). So you will need a fifth 1377 lb battery, maybe a sixth, larger motor ect. Then still you will need a larger generator to charge the batteries since there are no charging stations with that kind of capacity. Could be done if you were the winner of the last big lottery.
If the fuel tanks are gone, then that 12k lb weight is reduced around 350-400 lbs (with full fuel).
 
If the fuel tanks are gone, then that 12k lb weight is reduced around 350-400 lbs (with full fuel).
In my estimation I left the fuel tanks in since you will need all of that and more (possibly have to add the third tank modification) to charge the batteries from the Generator. At the full output of the Onan it will take 45 hrs of run time to charge the batteries using Teslas figures.
 
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In my estimation I left the fuel tanks in since you will need all of that and more (possibly have to add the third tank modification) to charge the batteries from the Generator. At the full output of the Onan it will take 45 hrs of run time to charge the batteries using Teslas figures.
Hmmm. Kind of defeats the purpose of having an electric GMC, if you have to haul 50 gals of gas around to keep it charged.
 
Another way to look at the math for this analysis, My '08 Cayenne S is about 5,000lb and gets about 20mpg on the road. With my 5,000lb Airstream attached, I get about 12mpg.

So, 455/TH425 ~1,100lb and 55 gal gas and tanks ~400lb = 1,500lb
Tesla Model S battery 1,200lb, Model Y 1,700lb Motor ~220lb
Model S motor and battery might be a 1:1 swap by weight....
You might get 180 mile range with the one "S" battery, however, using the "Y" or adding a second battery would exceed GVW
 
Using the Ford F-150 Lightning bolt as an example, and assuming you could put up with pulling 12,000 lbs with the motor in the Ford that was designed for 6015 lbs: The EPA estimate on the Ford is 0.87 kWh/mi (probably be twice that pulling 12,000 lbs) with a estimated range of 230 mi. I know two people that own these and they couldn't make it 75 mi to get to work every day in stop and go traffic which really takes a toll on the charge. The battery weighs over 1800 lbs. On flat ground you might get 110mi without adding a second battery. Of course charge times would be very inconvient.
 

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Using the Ford F-150 Lightning bolt as an example, and assuming you could put up with pulling 12,000 lbs with the motor in the Ford that was designed for 6015 lbs: The EPA estimate on the Ford is 0.87 kWh/mi (probably be twice that pulling 12,000 lbs) with a estimated range of 230 mi. I know two people that own these and they couldn't make it 75 mi to get to work every day in stop and go traffic which really takes a toll on the charge. The battery weighs over 1800 lbs. On flat ground you might get 110mi without adding a second battery. Of course charge times would be very inconvient.
We are now going on about 6 months with a couple f-150 lightning at work.

From my conversation with the drivers of the lightning last week, they claim The range seems to have dropped in 6 months. They used to get 240+ miles on a charge when brand new. Now they are struggling to get 200. And it is not winter yet. I think they are all 15,000+ miles on them.

I think the attempt is good…
But I just dont see the long term.
 
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