cub cadet rzt 50 weak left side

How to Fix Cub Cadet RZT 50 Lawn Mower Weak Left Side Problem? [5 Problems & Fixes]

Founded in 1960, Cub Cadet is a leading American company that manufactures a wide range of power equipment and services including utility vehicles and handheld products.

The company offers a massive lineup of zero-turn mowers, of which the RZT 50 is perhaps its bestselling model.

But just like any other product, the Cub Cadet RZT 50 isn’t perfect, and one of the biggest issues users experience is a weak left side.

I’ve listed 5 causes of a Cub Cadet RZT 50 weak left side and solutions to fix the problem.


Problems with Cub Cadet RZT 50 Weak Left Side and Solutions

1. Left side of RZT 50 is slower than the right

The wheels of zero-turn mowers are powered by two independent systems., and there are chances each can either malfunction or fail.

Attachments to your Cub Cadet RZT 50 zero-turn mower such as clipping bags and trailers can cause the left side to be slower than the right.

How to fix the left side of RZT 50 slower than the right problem?

  1. Start by checking the level of hydraulic fluid by using the dipstick located inside the fill cap. If the level of hydraulic fluid is low, top it up with the right fluid.
  2. After ensuring that you have the right amount of fluid, test if the lack of pull affects the left wheel in both forward and reverse.

You can do this by going up a hill in forward motion and backing up in reverse. If you feel a lack of pull in the left wheel, the bypass for the left hydraulic motor could be damaged.

The wheel bypass of the Cub Cadet RZT 50 is designed to let you push the mower by hand in the event of an engine failure.

Take a closer look at the left hydraulic motor and check for any signs of damage. Next, rotate the bolt sticking out of the left hydraulic motor so that its tight.

If doing the above doesn’t resolve the left side of Cub Cadet RZT 50 slower than the right problem, it’s time to have the mower looked at by the dealer.

2. Left Side of Cub Cadet RZT 50 Lacks Power

If the right side of your Cub Cadet RZT 50 mower is fine, but you’re getting minimal turning from the left side, and pushing the machine forward makes the machine groan, the cotter pin of the transmission release may be missing.

You should replace the cotter pin even though it’s not directly related to the issue, and then check the level of oil in the hydrogear oil filler.

How to fix the left side of Cub Cadet RZT 50 Lacks Power Issue?

The easiest way to fix the left side of Cub Cadet RZT 50 lacks power problem is by replacing the transmission drive belt. The left side always starts slipping when the belt needs to be replaced.

3. Left Transmission Stops Pulling After a Period of Mowing

In some cases, the left transmission may stop pulling after roughly 45 minutes of use. The first thing to check is if the transaxle is clean and the fan is in good condition. Adding to this, change the oil and see if this fixes the issue.

The most common cause of this issue is a fluid failure after it heats up. When the fluid boils, the hydraulic pressure drops, leading the left transmission to stop pulling.

Another cause of the issue could be a loss of the piston seal in the pump or motor due to distortion or galling.

How to fix Cub Cadet RZT 50 left transmission stops pulling after a period of mowing issue?

Try purging the oil and rechecking its level if the old fluid is burnt or discolored. If the oil is foaming, great chances are that the pump or motor pistons aren’t sealing.

Ideally, in this situation, I recommend speaking to your local Cub Cadet dealer the mower needs to be dissembled to figure out the root cause of the problem.

4. Left Side Getting Weak Especially in a Hard Cut

The left side at times may feel weak, especially in a hard cut and may get worse as the Cub Cadet RZT 50 mower heats up.

If your Cub Cadet mower is more than 5 years old, fixing the left side getting weak issue could be an expensive affair.

How to fix Cub Cadet RZT 50 left side getting weak issue?

Start by changing the oil and check to see if there are any signs of damage on the filter. Additionally, look underneath from the back of the transmission units to see if the filters have a cover on them to prevent damage.

Loosen the four bolts on the lower regulator to get all the old oil out but don’t completely remove the cover, just loosen it.

5. Cub Cadet RZT 50 Transmission Causing Weak Left Side

A weak or old transmission can cause the left or right side of the Cub Cadet RZT 50 mower to slow down during use. In this case, get the mower checked by a licensed professional.


Frequently Asked Questions

1. Why is my zero-turn mower weak on one side?

There could be several reasons why your zero-turn mower may be weak on one side including wrong traction adjustment, bad dampers, dragging drum brake, mismatched tire compression, or trapped air in the hydrostatic motor.

2. Why is my Cub Cadet slowing down?

Several causes for a Cub Cadet mower slowing down including bent or damaged belt idler brackets, or a worn idler tension spring.

3. Why is one side of my zero-turn mower not working?

First, check to see if the freewheeling rod is overriding on either side of your zero-turn mower. Next, check to ensure you have the right fluid level on the weak side of the zero-turn mower.

Final Thoughts

The Cub Cadet RZT 50 mower is a great machine but can break down at times. If you’re experiencing Cub Cadet RZT 50 weak left side issues, try the aforementioned 5 fixes or call your Cub Cadet dealer to get the mower looked at.