Hi all, recently my LS has started moaning with light vibration in the gas pedal when I'm at or below 40mph. This doesn't seem to happen when I accelerate quickly, but happens when I'm maintaining a speed of up to 40. Any thoughts why this could be happening??
Thanks.

 

This could be a number of things. Could be your tranny needs fluid replaced (specifically, Torque converter)... I had the same problem with an older car when overdrive first engages, and throws the engine in low RPM.

But also can be caused by something else. How clean in the tranny fluid? Does this only happen in the morning? or at anytime? oh and how many miles btw?

 

On mine, the resonance from the tires vibrates anything that is remotely loose. Also have a sound that seems like a spedometer cable but I think the LS is electrical opposed to mechanical. Similar sound the speedo cable in the Cressida made when the grease wore from the the cluster connection.

 

Thanks for replying. I don't know how or where to check the tran fluid. I'll have to refer to the manual. will get back to you asap.
I've got a 1991 LS 400 with 136000 miles on it. What does btw stand for?

 

BTW- By The Way.

 

I checked the trans fluid & it clear with amber/red hue. What do you guys think?

 

engine/trans mount perhaps?

 

Is there any way to check PureD?? Or where should I take it to get it looked at?

 

Also if that is the problem about how much should I get ready to spend?
Thanks

 

I think you need to get more specific with your symptoms.

Where is the sound coming from?

Smell your tranny fluid on the dipstick, does it smell burnt?

Could it be a possible wheel bearing going bad?

Sounds can be helpful if they are a little bit more specific as to location.

 

May be something as simple as tire rotation with tires re-balanced.

Also a good time for the tire inspection for uneven wear or cupping.

 

the symptoms are just too generic, it could range from wind noise to motor/trans mounts to rear axle boots to a whole host of other things.

 

Thanks for your input everyone. I got the tires balanced & alignment done. But there's still the sound. I'll get back to you guys on the rest of your questions.

 

The sound seems to be coming from under the car around the gas pedal area, with occasional vibration from under the hood on the drivers side close to the windshield.

 

It does sound like your driver side motor mount has crapped...just my opinion.