I did what you said and parameter 21 is set to 8. If I can get a can key do I want to go higher or lower to make it accept lower than 25 volts as a charged battery pack. I checked it again and the batteries are 25.3 volts at rest and 24.3 while lifting 4000lbs

Not with the keypad, use display and throttle grip. The Can key is a tool the Tech carries in his truck, it's never left in the lift. Basically a red box with a plug. You can change the first ten parameters without the Can Key. power off truck, hold down horn button while turning on key again. keep holding horn. Look at display, it will scroll betweem hours, codes, parameters. When "P" is showing, release horn button. Now twist grip and let go. You are seeing parameters 1 to 10. Actually you will see all, til 40....but you cannot change the ones over 40 without can key. Par 1 is top speed in slow mode, par 2 is top speed, par 3 is accel rate, Par 4 is decel rate. To change speed, when par 2 or 3 is on, hit the horn button. the Value shown will flash, now twist the handle grip to increase or decrease speed. Be carefull and make note of each parameter before changing. If you mess up things and the truck crawls, or goes too fast, you can put back to normal. A Raymond tech will have it, Do you know any?

How do you change parameters with the key pad? The is 2 wires with a plastic jumper and a round resistor looking thing glued to the side of the connector. Any chance that is the can key?

A can key is just a two inch square piece of plastic with a round pigtal. Yes, you change it by the throttle and display, but parameter 21 wont change unless you connect a can key, inside cab on top left. You can change other parameters like speed, without can key. Did you know how?
If you were not so far, i could lend you one. I could get to England faster than BC!

The problem started about a month after installing new batteries. Batteries are lead acid. Which was what was in it before. Battery cells are all even at 1275 sg. Batteries maintain 25 volts under load. At rest they are 25.5v at the line contactor. What is a can key? Is there any way to change settings with the keypad?

This problem started only after new batteries?
There is a parameter 21 for different types of batteries. It is from 1 to 20, with default at 8.
You need CAN key to change this
Did you replace with same type? Style?
What is voltage when you re-start....still at least 25.3?
May have a bad battery...so commom