Your comparing 3 forklifts from different manufacturers all with different load capacity's.
24 volt - 1.3 ton
36 volt - 1.5 ton
48 volt - 2.0 ton

Its easier to make the battery higher capacity & in turn more heavy which in turn keeps the counterweight smaller, this helps to keep the chassis as small as possible as that is basically what 3 wheel counterbalances are all about - manoeuvrability in tight spaces.

If it were me I skip the other two and go with the Clark.
24 volt is an obsolete voltage on sit down forklift trucks. 36 volt is strictly a North American voltage and not used in other parts of the world.
You should be able to get the Clark in either 36 volt or 48 volt. The advantage of the higher voltage is faster travel and lift speeds. If you have long runs and need a triple mast with 189" of lift or higher then I would recommend 48 volt. Assuming that you get the biggest battery that will fit in the compartment with matching charger then the 36 volt and 48 volt battery and charger package price is almost identical.

STICK WITH A CLARK , HYSTER OR YALE 36VOLT YOU WILL NEVER HAVE A PROBLEM WITH PARTS OR GETTING SERVICE AND THERE WILL ALWAYS GET YOU THE HIGHEST TRADE IN VALUE

We have taken the Heinrich out of the running because of the 24V. Despite the 48V we had to eliminate the Chery as well because it is actually a larger footprint. We really want to keep a nimble maneuverable three wheeler. So, the salesman for the Clark told us to check out the 36V from Mitsubishi. Waiting on a quote to see where it stacks up. The Chery comes with a great warranty as well. Any comments about a Clark vs. Mitsubishi?
As a side note we would be using the service from the company that supplies the Mitsubishi. Even if we buy the Clark we would still be using service from the Mitsubishi company. They are just better set up and closer. So I would prefer to give the purchase, which would be the Mitsubishi, to the company that we will be using for service. If the clark is simply a better unit though that is what we will get.

Take a look at Linde. They make a really nice three wheeler and they are super dependable. I'd still go with 48 volt. Once you get use to the speed you'll never use 36 volt again.

the higher the voltage the higher the amp draw. The higher the amp draw the higher the heat & the higher the owners electrical bill to run the charger. Heat is an enemy of electronic or electrical components - like motor controllers and motor brushes. 48 v is very commonly seen in forklifts in most countries around the world and 72 volt 7 80 v electrical system are no8 uncommon especially in the European market in larger capacity lift 8K & above. Today 24 volt systems in 3 wheel forklifts are just about non existent. The first three wheel units introduced to the US market were by Clark & they all had 24 v. Soon competition copied them with 24 v models. When folks started introducing higher volt units in the US market in 3 wheel models users were slow to change over - US folks like to do like waste money on energy consumption but taht is changing. My son an electrician is installing more 960 volt systems in buildings (new buildings and some retros). Europe is moving goi towards 1080 v for in plant use.

John- I think that this discussion has gotten a little to technical for Vinval as well as most of the general public looking for an opinion.
I'm assuming that you misspoke but if not... The Higher the Voltage, the Lower the amp draw. Fact.
I, like you, was in the business for many years and now am retired.
We almost exclusively sold 48 volt trucks while all of our competitors quoted 36 volt. Like propane, 36 volt is only a North American spec. Because our industry is soooo price competitive, the reason that our competitors quoted 36 volt is because they had the illusion that the corresponding battery and charger was cheaper than 48 volt which is not the case. If you price up an 800 ampere hour, 36 volt battery with a matching 3 phase charger, the price is within $50.00 of a 600 ampere hour 48 volt battery and matching charger. The kilowatt hours are identical. They both will do the same amount of work (or move the same amount of pallets per hour) but the 48 volt truck will do the work much faster. Once a typical customer uses a 48 volt truck, no matter what the capacity is, they will NEVER go back to a slower 36 volt unit. Because the industry is soooo competitive, you need something to set yourselves and for us it was 48 volt.

@duodeluxe
1. Yep I F/U but now I have corrected the errors. of my way. But from my vantage point i think my explanation was more on track in answering why their were voltage difference in the 3 trucks mention - two brands I never heard of but I've been out of the business 11 years. The Chines muck things up at times.
2.) Yes like you always presented the electric truck buyer with a proposal on 36 v units to provide them the same info "me too" sellers guess did and provided a separate proposal for the same unit with 48 v at the same $ but with - tangible customer benefits - then the discussions & demo begin (48v unit)began. Likewise, when a customer wanted a 5K cushion LP proposal I provided a 5K electric truck proposal w/48 v to show speeds were comparable and a ROI via longer economic life (7y vs 5y), lower routine maintenance, fuel savings and more environmentally friendly, and a 7 year $1.00 option contract or FVF lease and a possible greater depreciation tax deduction.
If my info went over the OPs head that is OK, they certainly have the option to ask questions. But in my book it is always better to provide more info than not enough -

I usually would not give options. I didn't want to compete with myself and didn't want to further confuse the customer from what the competitor(s) offered. Always quoted what I thought was best for their application.
The "Heinrich" is most likely a Jungheinrich which as a European company would only offer 48 volt. My experience has been that their parts pricing is way expensive and most US dealers have a major brand they represent and use Jungheinrich as a back up or fill in.

To each their own.
Never has been one way to close a deal - it all depends on what floats the boat of the final decision maker(s) and if a sales person has a relationship with them or not - organizations do play musical chairs every now & then Lot of folks will make you think they are but they ain't. Gotta' keep panning for gold.

Yep you are correct the Heinrich EFG 113 is an Jungheinrich probably sold by an MCFA dealer. The basic lift capacity is 2400 lbs and there are two 1920 lb models and a 2880 lb model in this family. The units are in fact all 24 V and no 48 v option and if I read correctly they are rear wheel drive units. Junheinrich offer 36 v/ 48 v units in their EFG213- 220 series (2510 lb to 3880 lb lift capacity series (front drive).

Right from the Jungheinrich product brochure

"EFG 110/ 113/ 115

Rear-wheel drive, compact design, high performance data and optimum ergonomically optimised working conditions - these are the strengths of our EFG"

After reading all of the great advice I recognize that the 48v would be a great machine. However, we are most concerned with maneuverability with this unit. The 48V is a larger machine. Plus we have never had an issue with speed, probably since we are only a 35,000SQF warehouse with a lot of machinery and inventory.
I believe it is all going to come down to the warranty and service at this point. Down to the clark and mitsubihis 3 wheel 36v units.

OK guys, I was thrown a curve ball today. One of the salesman came back with a 48V 3500lb Baoli. This unit has a lot of positives, 48V, its with the service company we would prefer and it is $5,000 less then the clark. Negatives is we have never heard of them. Any thoughts?

The Baoli is a Chinese built truck which is serviced and distributed in the US by Linde dealers. I expect that aftermarket service, parts and support is probably among the best of all of the Chinese trucks that are offered in the US.

Good to hear as the service is my biggest concern.

Toyota do offer a really nice 48 volt compact 3 wheel forklift with up to 2 ton lifting capacity - unfortunately its not available in the USA at the moment.

Its bigger European 80 volt 4 wheel brother is now available so maybe the USA will get the smaller 48 volt family of forklifts in the near future.