Vibration!

[86LK]

Ok so it’s not the wheels or tires. And I had wheel spacers on the rear 1/2 inch and I took them off and drove it. The vibration is much better but it’s still there. When I shift it in to neutral while it’s vibrating it goes away. What does that mean?

that it vibrates under load. what happens if you just coast while in gear at that speed?

I jacked up the rear and my passenger tire spins round perfect the driver side ever so slightly doesn’t spin perfectly round but I don’t think it’s enough to cause that vibration and even if it was it still should vibrate when I’m driving down the road and put it in neutral, but it doesn’t. The vibration goes away when I put it in neutral going like 40. Really sounds like an unbalanced driveshaft right? I looked at the driveshaft and there are weights on it I’m not sure how it would loose it’s balance

when you jacked it up, did you lift it from under the differential? or did you let the rear axle hang loose?
and while there might be weights on the driveshaft, that doesn't mean they are correct anymore. pull the driveshaft and have it re-balanced just to make sure (cheap insurance).

 

[69hurstolds]

Are the engine and trans mounts tight and in good shape? Throwing spaghetti on the wall here.

 

[78Delta88]

What transmission do you have?

Bad tire, flat spots, slipped belts will be there at all speeds. Drive slowly behind long building with windows down listen to the echo. You will hear the bad tire.

If you get vibration at single low speed spot and high speed spot its a harmonic. It is basically the Resonant frequency of the vehicle. You just have to rule out causes. Usually it's in the springs as they are unsprung weight.

Vibration under load but not in coast is typically a driveline issue. Think... "Driven Gear Train". This will be mechanical gears or clutches pushing against, rubbing against, or broken, or out of round, or broken or missing bearings, worn bushing causing excess lateral or rotational movement.

Main bearings going out you will not hear, but usually feel in the steering wheel. Rods, wrist pins, lifters you usually don't feel, you hear them. Rotational issues like, drive shaft, transmission, axle, and or wheels you feel in your back side or bottom, or as Forest Gump would say..., "buttocks".

Vibration in coast is typically driveline to include out of balance rotors, drums, wheels, spacers, driveshaft and basically anything rotating.

Engine rotation out of balance can be any thing to include harmonic balancer, flex plate or flywheel, and anything else that rotates. Old school you could remove one belt at a time, with current serpentine you can just remove it. Drive and see if vibration goes away.

Rule out engine, coast down hill and shut engine off.

Rule out transmission coast down hill with engine off in gear and then neutral or clutch disconnected.

On an automatic torque converter still turns until engine at 0 RPM, so you can listen and feel for that point. So prior to or after, is there a change. Coast in neutral, nothing is turning but the planet set and or drum/shell that is connected to the output shaft. Vibration still there or go away?

Old school when DIYing it, is to use two new worm clamps for clothes drier (4 inch ). Put on drive shaft, trial and error and definite pain in the b**t, yet you can move the worm clamps toward or away from each other until you find balance point if it's a drive shaft problem. Better yet is just remove the shaft, R@R the U-Joints and have it rebalanced as previously suggested.

Coasting down hill lightly apply brakes. Vibration reduce or go away? It's rotors or drums, or something connected to rotors or drums.

If e-brake is good, coasting down hill apply e-brake very very carefully. If vibration goes away, typically it's drums or something connected to them, or rotors if you happen to have 4 wheel disc brakes.

If your trans has removable rear housing, you can remove and change out bushing and seal. Check the yoke for excessive wear and check the output shaft while still installed for excessive play. Th200 and 2004R you can't do this, but TH 250, 350, 400, 700R4, 4L60(E) and 4L80E you can.

 

[Rt Jam]

. When I shift it in to neutral while it’s vibrating it goes away. What does that mean?

Have you tried anything mentioned yet?

A driveshaft is easy to diagnose. Support rear axle housing on jack stands. Remove wheels and drums.
Spin drivetrain up to speed and report back vibration or no. Do not touch brake pedal with drums off.
When you are done, kill engine and wait until axles are stopped before going back to Park.

 

[spongbob]

Could you have NGK spark plug/s in your motor ? if so jerk them out get some champion "... er AC....next Jack up the rear tire/s (off ground about 1/4")put car in neutral scotch front tires take a can like porkenbeans (food)come in and set it near the tread till it about touches the surface ( warm weather after driving a Mile or two) rotate the tire and watch the can'..where its almost rubbing the tire ...on its surface (tread area) ...if the can is moving set it back say 1/16" then turn the tire in a circle. Watch what happens to the can and it's reletive distance (close proximity) to the rotating tire (rotate by hand)..preferably you should be close to the tire as possible without it actually moving the can .thus action allows you to tell how much out of round your tire is and or some rim defects less often...okay here's what to decide...got 1/16 " or less keep your tire...got 1/8" deviance in the tread parameter? Live with it or get good brand tire .Got 3/16" variant in tread symmetry? You got a traveling disaster waiting to happen..if the rear passes this inspection do the front as tires act like sea saws.. hope this helps someone if not thanks,if the rim itself is bent or off center you will need to pay attention to the turned (formed) base at the point were the tire hole (centering) occures . I have tried to discern this with the rotating and some kind of pointer from inspection of the rim flange but don't quote me here please.When it come to tires brand matters by the way how's your front control arm bushings doing ?

 

[Clone TIE Pilot]

What transmission do you have?

Bad tire, flat spots, slipped belts will be there at all speeds. Drive slowly behind long building with windows down listen to the echo. You will hear the bad tire.

If you get vibration at single low speed spot and high speed spot its a harmonic. It is basically the Resonant frequency of the vehicle. You just have to rule out causes. Usually it's in the springs as they are unsprung weight.

Vibration under load but not in coast is typically a driveline issue. Think... "Driven Gear Train". This will be mechanical gears or clutches pushing against, rubbing against, or broken, or out of round, or broken or missing bearings, worn bushing causing excess lateral or rotational movement.

Main bearings going out you will not hear, but usually feel in the steering wheel. Rods, wrist pins, lifters you usually don't feel, you hear them. Rotational issues like, drive shaft, transmission, axle, and or wheels you feel in your back side or bottom, or as Forest Gump would say..., "buttocks".

Vibration in coast is typically driveline to include out of balance rotors, drums, wheels, spacers, driveshaft and basically anything rotating.

Engine rotation out of balance can be any thing to include harmonic balancer, flex plate or flywheel, and anything else that rotates. Old school you could remove one belt at a time, with current serpentine you can just remove it. Drive and see if vibration goes away.

Rule out engine, coast down hill and shut engine off.

Rule out transmission coast down hill with engine off in gear and then neutral or clutch disconnected.

On an automatic torque converter still turns until engine at 0 RPM, so you can listen and feel for that point. So prior to or after, is there a change. Coast in neutral, nothing is turning but the planet set and or drum/shell that is connected to the output shaft. Vibration still there or go away?

Old school when DIYing it, is to use two new worm clamps for clothes drier (4 inch ). Put on drive shaft, trial and error and definite pain in the b**t, yet you can move the worm clamps toward or away from each other until you find balance point if it's a drive shaft problem. Better yet is just remove the shaft, R@R the U-Joints and have it rebalanced as previously suggested.

Coasting down hill lightly apply brakes. Vibration reduce or go away? It's rotors or drums, or something connected to rotors or drums.

If e-brake is good, coasting down hill apply e-brake very very carefully. If vibration goes away, typically it's drums or something connected to them, or rotors if you happen to have 4 wheel disc brakes.

If your trans has removable rear housing, you can remove and change out bushing and seal. Check the yoke for excessive wear and check the output shaft while still installed for excessive play. Th200 and 2004R you can't do this, but TH 250, 350, 400, 700R4, 4L60(E) and 4L80E you can.

For transmissions with nonremovable rear housings there are special puller tools that can pull the end seal and bushing without removing and diassembling the entire transmission.

 

[SoFloG]

Could you have NGK spark plug/s in your motor ? if so jerk them out get some champion "... er AC....next Jack up the rear tire/s (off ground about 1/4")put car in neutral scotch front tires take a can like porkenbeans (food)come in and set it near the tread till it about touches the surface ( warm weather after driving a Mile or two) rotate the tire and watch the can'..where its almost rubbing the tire ...on its surface (tread area) ...if the can is moving set it back say 1/16" then turn the tire in a circle. Watch what happens to the can and it's reletive distance (close proximity) to the rotating tire (rotate by hand)..preferably you should be close to the tire as possible without it actually moving the can .thus action allows you to tell how much out of round your tire is and or some rim defects less often...okay here's what to decide...got 1/16 " or less keep your tire...got 1/8" deviance in the tread parameter? Live with it or get good brand tire .Got 3/16" variant in tread symmetry? You got a traveling disaster waiting to happen..if the rear passes this inspection do the front as tires act like sea saws.. hope this helps someone if not thanks,if the rim itself is bent or off center you will need to pay attention to the turned (formed) base at the point were the tire hole (centering) occures . I have tried to discern this with the rotating and some kind of pointer from inspection of the rim flange but don't quote me here please.When it come to tires brand matters by the way how's your front control arm bushings doing ?

What's wrong with NGK plugs?