Car acceleration occurs when the rear wheels exert such a force against the ground in a horizontal direction that it makes the car to start accelerating. When the car is usually in slow-motion, more than half of the force goes in the acceleration of the car.
If your car shakes when accelerating there could be many reasons for it to occur. Mostly cars shake when they’re trying to give a warning at the first stage, so if the problem is capable of increasing, you can fix it before something bad happens to it. Now there are two situations when a car can shake during acceleration. One is when you are driving and one when you stop the car.
Reasons for Car Shakes When Accelerating
1. Unbalanced tires
First of all, Unbalanced tires can be a reason why your car shakes during acceleration, and that mostly happens when you get new tires, and they don’t get properly fixed or balanced. When tires get mounted on the wheel, they never the same mass all the way around. When a tire rotates, any weight imbalance will turn into a tiny vibration.
At much higher speeds where the tire is rotating much faster, the shaking will be more observable, and your steering wheel will actually shake. When your car vibrates at a constant speed and is far more bad at higher speeds, you may have an unbalanced tire. It’s also possible one of the wheel weights fell.
2. CV Joint
There can be an issue with the CV joint, it can be damaged and causing shakes in the car. They are located mostly at the end of the axle points, and there are two joints, outer and inner. When the inner joint gets damaged, you can observe that the car starts shaking under hard acceleration.
When under load you will notice that the shaking will get worse. Because of wear and tears in the joints, CV joints can get damaged and cause failure. When stuff like this happens, to water and dirt gets inside the joints boot and poison the grease that is protecting the splines inside. The metal on metal contact eventually causes failure because of no proper lubrication and too much friction.
3. Broken motor mounts
These are also the reason for car shakes during acceleration. The main function of motor mounts is to stick a vehicle’s engine to the frame of the vehicle.
A secondary purpose is to reduce engine shaking, so the owners of the car don’t feel the constant vibrating of the engine while it’s on. Engine mounts are made up of a hard rubber which allows them to absorb these shaking.
When a motor mount is damaged, not only will you feel a lot of shaking motion in the car, other parts in the engine can get misaligned and eventually break since the engine is not in its specific location. You can be able to observe while idling that the motor mounts are not functioning properly, but shaking is more obvious during acceleration in the car.
4. Loose lug nuts:
It seems like a simple problem, but it can lead to far worse issues. If lug nuts are not loosened or torqued up over time, the wheels will become shaky and while driving it will seem like the car is shaking. If the nuts are left untightened, the nuts could ultimately loosen all the way out, and your wheel could fall off while driving. You don’t want that happening. Don’t stop making sure that you’re using the correct nut size as well.
Bent driveshaft if your car has rear- Wheel drive, power from the engine to the rear axle and connected wheels is delivered through the driveshaft. If the driveshaft is even slightly bent or damaged mostly due to accident, it will cause the car to shake when accelerating at low speed and get worse as you make the speed higher.
5. Loose Wheel Bearings (Driving)
Wheel bearings grease the wheels of your car to protect them from generating heat. If the wheel bearings become loose, you will observe shakiness coming from the wheels. It will also make your car less stable.
6. Bent axle:
If you have a minor accident and you don’t see any observable damage don’t ignore it. The accident could make the axle bent, and it can cause severe shaking in your car. Then you will start noticing shakings in your car which will get worse over time whenever you accelerate the car and will give a lot of damage to the car if not fixed in time.
7. Stuck brake caliper:
If your brake caliper is causing stickiness to the wheel and is enabling faults. Then it will cause the car to shake. In this specific situation, the steering will start shaking while reaching 40-50 mph. The shaking will get worse when you accelerate at high speeds continuously. And when your car stops a burning odor will start coming out.
8. Disconnected vacuum hose:
While driving your car this will cause a lot of shaking and shuttering in your vehicle. If your vacuum hose is disconnected and develops an air leak due to some wear and tear, the lack of air pressure can cause sensors to get mislead and cause fires and losing power etc.
9. Worn spark plugs:
Spark plugs that are fouled up cause engine to backfire. Usually, you come to discover the problem when the car is at a stop. And it will seem like the car is shaking while you are driving.
10. Worn tire treads:
Each tire has trodden on them, which makes them grip the ground and obviously it makes the car more stable and structured. Anyhow treads on your tire are the most vulnerable areas in your car and they can get affected easily. Because the tire treads constantly work when you are driving as they rotate when the tires do. Eventually, they can very quickly get flat and out of the texture. Your car will experience a lot of shakiness which will get more intense when you accelerate faster.
11. Loose wheel bearings:
Basically wheel bearings stop your tires from friction and make them greasy to stop the vehicle from generating heat. When these bearings become unbalanced and lose your car experiences shakiness, it will also make your vehicle unstable.
12. Bad propeller shafts:
Propeller shafts deliver power from the engine to the wheels. If your propeller shafts become faulty, they make your vehicle vibrate and shake altogether.
Read if you need: Car Shaking When Stopped
Solutions of car shaking when accelerating
1. For your joints:
You need to remove the driveshaft and feel the movement of the CV joints. You will need a visual diagnosis first then you will check the greasiness between the joints. The mechanic will obviously check your CV joints, but in the case of these, you need to replace both joints from scratch as they need to be replaced when they stop functioning properly every time.
2. Tires unbalanced:
It can also cause issues as discussed earlier. To fix them you will need a jack, a flat end screwdriver and a lug wrench with the help of a balancer. You will have first to remove the wheel weights then remove the wheels and clean them. Balance the wheels in the marked spots and put the weight back on. Recheck and adjust the wheels. Return the wheels back into position.
3. For spark plugs:
You need to locate the old spark plugs first. Then you would have to remove the spark plugs and measure the gap between the plugs. Install new plugs after that. As a good driver, you must be sure that the plugs are correct.
4. Tie rod ends:
To remove the problem regarding tie rod ends you need to access them first locate them and then remove them carefully. Then you will replace the tie rod ends of the same length and thickness.
5. For clogged transmission filter:
You need to secure your car while you are working underneath it by jacking up the vehicle. Then you will drain the fluid in a bucket underneath the car. Remember to use socket wrench for this work. Then clean the pan by removing bolts and old gasket seals, and you can use a scrapper also to scrape any dirt and debris on the filter. Then you will install a new pan gasket seal. In the end, change the transmission filter.
6. For low transmission fluid:
First of all, you need to keep the engine idle. Many people add fluid when the car is still running, and that is not healthy. Add the correct transmission fluid by checking all instructions first.
As there are specific fluids for every engine, you need to investigate which one is right for your engine. Then pour the fluid into the transmission, use a funnel for the dipstick, so there is no overfill. Then depress the brake and remove the transmission. To make sure you get the right reading. Then return the dipstick back into the transmission hole. In order to lock it into a place, you would need a latch.
Summary:
In order to avoid any car vibration and shaking during acceleration you need to do certain things: you need to get your car regularly checked and inspected by a professional, but ideally the owner should take care of it as much as possible. Always keep your tires inflated at an appropriate tire pressure so you can secure insurance of your tires for as long as possible without any deformation and uneven wear.
Replacing suspension parts is also the type of maintenance if you are buying good quality parts and getting them fixed properly too. No car can last for long if the components are cheap and second hand. You can also keep your costs at a minimum by giving your car as much love as possible, keeping the standard speed limit and also getting its service done monthly. Worn Cardan joint also causes shaking in the car during acceleration.
If you face problems regarding that, you need to pay attention to driver shaft, cross pieces and hanger bearings. Fixing them can fix the problem. Worn out bearings also cause shakings, and they need repair, and it’s not worth delaying. It will lead to disastrous consequences. For diagnostics hang the wheels and shake them in transverse and longitudinal directions. Free play is a sign of replacement. It is also necessary to pay attention to the clutch and gearbox because they can also be the reason for car vibrations during acceleration. For proper diagnosis, you will pay attention to the factors of appearance of vibration and beats.
If vibration is observable at 40mi turn on first two gear then 3. In this way, you can precisely determine the components of the gearbox. If you find any deformation in the gearbox, the shakings will be noticeable at acceleration on any gear. You need to check the level of indicator and gear etc. also the oil levels for proper check-ins and repairs.
Related post: Car Shaking When Braking at High Speeds
Final Thoughts
So, we tried to point out the main faults that lead to the shaking of the body or the engine when accelerating. Now we can make a diagnosis or go to the specialists. In any case, do not forget that a serious vibration is an important problem, and therefore it is not recommended to ignore such problems.
In case a car shakes when accelerating, in motion or even idling, it is vital to search for the issue quickly. Otherwise, everything can lead to an accident or a failure of one of the expensive engine parts. All parts need regular checkup and repairs, so you don’t face long term problems with your vehicle. It is really necessary that your vehicle gets inner and outer service at least once in two months. That will include outer maintenance as well and inner as well. Your engine will be thoroughly inspected, and your tires will be either changed or repaired.
Your tire treads should be really tough, and after every long drive, you need to check your gas levels, tires and oil/fluid levels. If your car is in good form your whole life will be in peace because you can’t travel anywhere without your car easily even if it is a ride to the mall or your office or the hospital.