IMO usually when the weight is tranfered the wheel that unloaded spins. IMO this could be either rear wheel (right or Left) When you by new mower make sure it has locking rear end. These are usally on high end models (5K or more LTs).

Thanks for the advice. My current lawn tractor is a 1991 lowes model made by MTD. It only drives via the right wheel. I imagine it was a lot cheaper to produce and for a flat yaard such as I had in Ohio it served me well. Not so in the hilly area we live in now.

I truly think that maybe the drive key has fallen out of the axle where the wheel goes on it! Did you have the "undriven" wheel off of it lately? Did you find a greasy square piece of steel laying in the grass, driveway, or garage floor?
Most lawn tractors have both rear wheels under power when going along mowing. The amount of "slippage" that happens with a heavy vehicle, used on pavement, is a concern, and thats why your car or truck, whatever, has a geared differential. Lawn tractors, etc. that are power driven, do not usually have a differential, as the slippage of two driven wheels, in a turn, is overcome by the grass or dirt it is being driven on. A concrete driveway or garage floor is not a problem, at slow speeds.

??? I think I'm hearing the music to the "Twilight Zone" in the background while I read this? IMHO small LT, GT tractors have differentials and the wheel that is slipping is the one that spins, be it left or right. At least that's the way it is on everything I have around here or have used in the past. Admittedly, haven't been exposed to the low end stuff.

Ev

It good to know that modern LTs use a differential and drive both wheels. Thats one less thing to be concerned about as I shop around.

My old 1991 unit is a low end model sold by Lowes and it drove the right wheel only. Its only became a problem when we moved to a new home on a hillside.

Thanks for the responses.

Jack

Lakeguy - I doubt that your 1991 tractor only drove right wheel only - ever. Either it was missing one of the square keys that resides in the axle and wheel hub joint or - after you got the new home with the hillside - the tractor was being driven across a slope that caused the machine weight to shift to one tire, allowing the other to easily spin.

To exmar's point - L&G tractors have a differential. It is what allows them to turn sharply while being used without the back tires skidding/resisting.

I too am somewhat skeptical of the existence a 4 wheeled tractor wherein the locomotion of the machine is affected by a single drive wheel.
I'm not saying it has never been done, I'm simply stating that I have never encountered, nor heard of one.
Basically, if the machine features a rear axle case assembly that provides the mounting points for both of the rear wheels...........there would (or should) be a differential assembly inside that axle case.
A non-locking differential (standard of industry) divides the propulsion effort equally between the 2 drive wheels and each wheel has 50% of the power going to it. So long as the ground surface affords an equal "bite" the machine will move in the desired direction of travel.
But.......if the "bite" or traction of either tire falls below a certain threshold amount.......the tire that has the most traction will stop turning and the tire having the least traction will begin spinning fruitlessly.
LOCKING DIFFERENTIALS can defeat this "shift of power" by preventing the differential gears from turning inside themselves (which is what happens in a wheel spin situation or when making normal cornering turns).
If there has ever been a "right drive only" lawn tractor a photo of the propulsion system would certainly be nice.

Rusty Jones had a senior moment when he said that lawn tractors don't have a differential in the rear axle! His 88 year old brain passes gas occasionally! Please excuse my gaffe! RJ

Rusty - not to worry. Believe all of us have one of those t-shirts someplace...

***"Believe all of us have one of those t-shirts someplace..."***
I was wearing mine yesterday.
I recently bought a used late model Chevy pickup truck which only had one ignition key. The key has a "micro chip" embedded. The cost for an additional micro chip key is over $50 at a GM dealer. But, I can get a chipless key made for less than $10......but it will only unlock the doors......it will not work for the ignition key because unless the computer reads the correct code from the key......vehicle no start.
So, I got me a chipless copy for in case I mess up and lock my keys inside the truck.
I have my ignition key on a fob all by itself.
I carry the chipless key on a different fob with other keys.
Yesterday while out running errands, I returned to my truck to head back home and wouldn't you know it. My truck would not start. When I turned the key nothing happened, but a message on the instrument panel said "SERVICE THEFT DETERRENT SYSTEM".
I immediately got a bad case of despair.
I called a friend who lived nearby and was familiar with late model GM products and explained to him what was going on. He asked where I was and said he would come right over to see if we could "reset" the system using the GM field procedure for that.
When he got there and I showed him what it was doing was when I realized I had put the chipless copy into the ignition switch and I started apologizing to him.
He just grinned and told me to put the chip key in and try it. I did and the truck started right up no problem.
He said that he had not had his senior moment for the day yet but he was sure it could not be far off.