1998 dodge ram 1500 a/c cuts out under load

Stops blowing cold you mean? If so then your system may be low on freon or the compressor may be getting weak. There are systems in your vehicle that cuts the ac off under heavy throttle to give the most power, but this shouldnt occur in normal driving conditions.

I also have a 1998 Dodge 1500 and had the compressor changed a few weeks ago, but the A/C still cuts off when under almost any load.

Check your vacum lines and vacum check valves. I had the same issues a few years ago. Under acceleration the vacum level changes allowing a shutter to close blocking off air flow. I didn't find the problem so I can't explain it in detail.

is there a bypass for this problem. need cold air more than acceleration.

yeah thats exactly what I need too

There's a switch behind the glove box that you can either lock open or lock it shut if you lock it open it'll never shut it to cut the air off