QA

Question: How To Balance A Driveshaft

How do I know if my drive shaft is out of balance?

Signs of a bad driveshaft/drivetrain Vibrations from under the vehicle. A common symptom of a failing driveshaft is an intense shaking coming from underneath the vehicle. Difficulty turning. Loud clunking noise. Car shudders upon acceleration. Squeaking noise. Clicking or knocking noise.

Can you rebalance a driveshaft?

Dented drive shafts cannot be rebalanced, they need to be replaced. Fortunately, you can fix minor imbalances by balancing the drive shaft, a procedure that requires minimal parts — only hose clamps.

Does a driveshaft have to be balanced?

Driveshaft components like CV joints, U-joints, and yokes accommodate axial movement and allow for variation in driveline angles and distances between components. Like tires, your driveshaft should be balanced to promote safe operation and prevent failure.

What happens if driveshaft is out of balance?

A First order driveshaft vibration will cause one shake or disturbance for each revolution of the driveshaft. IMPORTANT: Anything that is out of balance will only cause a first order vibration, never any higher order vibrations. A component rotating the same speed as the driveshaft that is out-of-round.

How does a driveshaft become unbalanced?

Undercoating, mud, or a missing balance weight cause the driveshaft to spin out of balance. It results in a vibration that increases with vehicle speed. Universal Joints: Worn U-Joints are most noticeable while accelerating and decelerating. The most common cause of U-Joint replacement is lack of lubrication.

What does an unbalanced drive shaft feel like?

Common signs include intense car vibrations and abnormal noises, like clunking, rattling, and scraping, coming from under the vehicle.

Can you put a driveshaft in wrong?

The 2 piece shaft guys have a slip yoke in the middle. If they split the shaft and not re install it correctly, they will throw the shaft out of balance and cause an uncomfortable vibration.

Can wrong pinion angle cause vibration?

In your case, it appears that the pinion is operating at an intersecting angle to the driveshaft. This will cause a vibration at speed. The reason adding weight with a passenger affects the vibration is that the intersecting angle has improved, but not eliminated, the problem.

How do I know if my slip yoke is bad?

Grinding and squeaking sounds from the drive shaft are frequently caused by worn universal joints. The joints become dry, causing the rollers to wear. Clunking sound, when going from acceleration to deceleration or deceleration to acceleration, may be caused by slip yoke problems.

At what speed does a driveshaft vibrate?

Driveshaft balance issues can generally be felt at vehicle speeds over 30 mph. shaft. A component that’s out-of-balance will never cause a second or higher order vibration, only a first order vibration.

Can driveshaft cause vibration?

A bent or damaged driveshaft can result in vehicle vibration. On rear-wheel vehicles, the driveshaft will rotate two and a half to four times the speed of the wheels. Due to the relatively large size of the rear-wheel drive shafts and high speed, vibration is significantly increased.

How long do driveshafts last?

While there is no set lifespan of a driveshaft, it typically can last about 75,000 miles. Keep in mind depending on the vehicle, and wear and tear you may get much less or much more.

Do FWD cars have driveshafts?

Front-wheel drive (FWD) On a front-wheel drive vehicle, the front wheels provide the power. Instead of having a long driveshaft like on a rear-wheel vehicle, all the drivetrain components are in the front of the vehicle. Rather than using universal joints, this setup uses constant velocity (CV) joints.

Why is my driveshaft making noise?

Another symptom of driveshaft issues is loud clunking noises. These noises are usually produced by worn-out u-joints. The ability of your driveshaft to rotate correctly is altered if your vehicle has a faulty u-joint. Lack of u-joint lubrication can cause squeaking noises when you drive at low speeds.

Does it matter which way a driveshaft goes?

Actually, it does matter which way the yokes are installed, and 90 degrees is not the way to go. Correctly oriented universal joints are said to be in phase (as illustrated below).

Why do you mark the driveshaft components prior to removal?

When someone mentions marking a driveshaft they are talking about the the slip yoke when removing it from the splines. You need to make sure it is put back on the same way it came off. If its not, you will get vibrations.

What angle should a driveshaft be?

Ideally, both driveshaft-operating angles will be 1 to 3 degrees. Anything over 3 degrees at the rear axle will shorten your universal joint’s life and could create vibration. If your angle is larger than 3 degrees, you must make sure not to exceed max driveshaft RPM as shown on this Spicer table.

What is driveline shudder?

Driveline launch shudder is a second-order vibration phenomenon excited by the driveline system in vehicles. It is experienced as low-frequency tactile vibrations at the vehicle seat track and is further deteriorated by a high torque demand from the engine.

Does the driveshaft spin in neutral?

Normal, if your transmission is in neutral and you spin the driveshaft, the input shaft will not spin.

How much play should a drive shaft have?

3/4″ of rotational play, or slack measured at the outside edge of the u-joint flange? I would say that is fairly normal, but if you are having noise from the rear end, I would be pulling the cover off and have a look inside. Remember, it could be coming from a worn wheel bearing too.

How far does a slip yoke go into transmission?

DD: The slip yoke should be able to go into the tailshaft of the transmission so the barrel is fully inside the seal. Then, pull out the yoke 1 inch. This is the correct amount of spline contact for the slip yoke.

Why does my car shake when I reach 70 mph?

The shaking is typical of a tire that is out of balance. Tires are balanced with metal weights. Over time, weights can come off. The other possible problem is that one of the tires is damaged and has a cord separation, which could cause the vibration and lead to a tire blowout.