I think the only electric golf car that uses a 36-volt system is E-Z-Go. I own two E-Z-Go carts and have found no disadvantage in range as the result of their chosen power source. My carts both attain the maximum legal speed of a little less than 20 mph. And both carts have a range of about 40 miles.
Among those manufacturers using a 48-volt system, only Par Car claims that it results in a longer range--60 miles, as recall. Some of the competitors challenge that, but that debate is for another day, I think.
I would suggest that the following be considered when choosing between the two power sources...
- E-Z-Go is the largest golf cart manufacturer in the U.S. by a good margin. If there was a particular advantage to changing from a 36- to a 48-volt power source, it seems to me they would have done it long ago. The cost of such a change for E-Z-Go would be a miniscule addition to their costs.
- The 40-mile range of the E-Z-Go has been tested using GPS units quite often here in TV. It is a completely valid claim. Remember, if you modify a cart to go faster or constantly use the headlights, those actions can reduce the range of any golf cart quite noticeably.
- Lastly, when considering the range question, think about how you might use your cart. Driving around TV you'll have a hard time averaging more than about 10mph. With a cart that has a 40 mile range that means your fanny would be sitting in your golf cart for four hours. For a Par Car, six hours! Are you going to be driving around anywhere near that amount of time in a day? If not, the question of voltage and range is a bit inconsequential when comparing electric golf carts.
I hope this helps.