Vibration and shake at Idle (35 Viewers)

[Trunk Monkey]

Have you removed the roof rack bar or tightened it? If you identified it, I don't understand what you're still chasing.

 

[2001LC]

I could try that but haven't as it's my "check engine light/sound" one could say. It tells me something is wrong. I've managed to reduce frequency from 100% of time to 10% by doing the things I've stated, but now hearing it more frequently with temperature change. Which I feel could help find my that last 10% of cause.

So that's why I'm asking what does temperature affect?

 

[Trunk Monkey]

So you're presuming that because a roof rack bar is vibrating that something is wrong elsewhere on the truck? That's a leap I wouldn't make. Vehicles create vibrations and harmonics. Enough so on the 100 that they added a damper to the frame. Sometimes my plastic engine cover vibrates, sometimes it doesn't.

 

[2001LC]

Not presuming, roof rack tight and have had LC for 10 yrs, I'm very attuned to sound(s) of my LC. This vibration started very recently and going through mud on the issue it's common and not been solved ...yet

OH and flux capacitor's on frame for over ten years and mounts good.

 

[Grundletaint]

Mine rumbles/vibrates while stopped and tach is at 600 RPM. If I inch forward a little bit it'll keep vibing until it moves forward enough to get engine past 600 RPM then it stops. Pop it into neutral and it idles at 800 with no vibration. Go up to R and it goes back to 600 with the vibration.

 

[2001LC]

That's^ the "D" vibration.

I really think what we're dealing with is a number of smaller issues. One of which has to do the with the fuels we have to deal with in to-days' market. That said: Right now I'm focusing on the fact engine and/or transmission temperature seems too make a difference, the higher temperature the less vibration. Also the outside air temperature, it seems; as temp gets colder I have more vibration, and as the day warms less vibration. Not only sound but feel through steering wheel.

Looking for input as to what systems are affected by Temperature......

TM gave some, anyone else have any ideas along these lines.....?

 

[SWUtah]

Mine rumbles/vibrates while stopped and tach is at 600 RPM. If I inch forward a little bit it'll keep vibing until it moves forward enough to get engine past 600 RPM then it stops. Pop it into neutral and it idles at 800 with no vibration. Go up to R and it goes back to 600 with the vibration.

That's mine, got down into 40's-50's more vib,s at lower temps, but it is a badass truck that is designed and built to last for 25 years in a third world country or Detroit

 

[2001LC]

Yes they are tanks, and aging better than most vehicle's on the road.

I'm of the opinion; E85 gas along with the summer to winter gas formula is a contributor to this vibration issue.

But why would temperature seemingly for many of us make a difference?.... What are the part most affected by temperature that would effect idle????

 

[FJ62INTX]

colder temps, things are tighter, rubber is stiffer, less play in bushings and engine mounts, cold rubber is stiffer and thus may cause more vibration than when warm, engine and tranny oil viscosity is also thicker up to full operating temp.


I am not against the theory that the gasoline's alcohol content may contribute to this also.

I wonder, has anyone tried softer exhaust system rubber hangers?

And/ Or installing some Exhaust flex joints in the system to reduce the engine vibration that is being transmitted by the exhaust into the chassis?

 

[2001LC]

To be clear "D" vibration is only after warm up when temp gauge and rpm indicting normal operating temperature.

All good points FJ62, and I might add; when running engine hard it stop vib. This would be when op temp above what we'd get when driving normal. Although can't see difference on temperature gauge. I can tell running hotter; by checking fluids especially transmission fluid, it show slightly higher on dip-stick than when at normal op temp.

I need to re-check those exhaust hangers, thanks.

Any thoughts on a specific meters/sensors/components that would affect idle positively when engine hot and negatively when not, and same when hot or cold outside temperatures exists?

 

[bluecruiser]

Is this like one of those trick threads that will never end because of the question at the end of each post? (Look, I'm keeping it going)

 

[paflytyer]

I need to re-check those exhaust hangers, thanks.

Do you have a stock rear bumper, or aftermarket?

 

[2001LC]

stock

 

[SWUtah]

Do you have a stock rear bumper, or aftermarket?

anyone else having a problem accessing mud?

 

[jonharis]

anyone else having a problem accessing mud?

I find it to be not very accessible at times....

Clean the TB. Balance the tires. Ensure there are no lose parts or accessories.

 

[FJ62INTX]

I was tugging on my exhaust the other day and it is rediculously tight with no give at all on the rubber hangers.... Like, I can put all my 280lbs (yes I am a fat azz) and it doesn't budge...

To me, that means the exhaust is mounted way too stiff to the engine and to the frame by the rubber hangers...

I may see about supporting the exhaust and removing the rubber hangers to see how stiff the exhaust is without them....

 

[paflytyer]

stock

Is your spare tire tight?

 

[bluecruiser]

Is your spare tire tight?

my mind has been churning about this all day. Maybe there is a loose piece on your license plate frame? Damn. I'd like to figure this out.

 

[adrenalinefjz80]

Mine rumbles/vibrates while stopped and tach is at 600 RPM. If I inch forward a little bit it'll keep vibing until it moves forward enough to get engine past 600 RPM then it stops. Pop it into neutral and it idles at 800 with no vibration. Go up to R and it goes back to 600 with the vibration.

I had this scenario for 1 year in my daily commute. It happened mostly in cold weather temps below 50. After replacing the motor mounts, I've never encountered it again.

 

[2001LC]

Good to know, how long ago were they replaced and was there visible movement.

Others did same, but said came back after a year or so.