Hi,

I bought a new 2008 RX400h AWD in December 2008. It is a pretty good deal by that time.

However, I did not feel very good driving it. Whenever I do mild acceleration from stop to 40M/h or drive uphill on a local road at around 30M/h, the power meter reading is at around 10 - 35 KW, the gas pedal shakes my foot and the steering wheel does not feel solid, actually, the whole car shakes a little, including the carpet and seat. I took the car to the dealer a couple times, also test drove with a Lexus representative twice, after the first test drive, he recommended road forced tire balancing, after that, the steering wheel feels better, but the shaking gas pedal still bothers me. I drove his 400h for a little while, barely felt any vibration from gas pedal. The second time, Lexus representative test the car with a device called EVA (Electronic Vibration Analyzer) and compared to his 400h, told me that the reading is EXACTLY the same, nothing wrong with mime and nothing he can do about it.
I do not know exactly where he measured, probably some power-train components as I thought the vibration was caused by power-train.

He also told me that it is the characteristic of Hybrid, and my car has not been broken-in yet (currently has 2000 miles). To me, it sounds like excuse.

However, the showroom demo (with 500 miles) and his 400h (with 3000 miles) do not have this problem.

Did anyone have similar experience with a brand new 400h? Any solution?

TIA!

 

I am beginning to think you have Good (BAD) Year tires if you do see if you cannot get them to change them ASAP Check this thread on them https://www.clublexus.com/forums/rx4...000-miles.html or https://www.clublexus.com/forums/rx4...338-tires.html
I had Good (Bad) Year on my Prius with similar issues vibration,front end wander and no traction in rain.

 

Thanks for the tip.
Yes, I do have good year tires on my 400h, I knew it was bad and had asked the dealer to swap them, probably was not firm enough as I got a really good deal by that time.

Since most 400h come with good year, I should not be the only one experiencing this if it was the tire. Anyway, I will try to get rid of it.

 

Yes i also have the same problem, the vibration comes through the gas pedal/steering wheel and seat. This appears when the engine engages and as you say up hill or under pressure. It clears when the car gets above 40 mph. I have asked that the area manager has a look at it, will let you know what he say's when I see him. Like you I think it is the drive train. My garage has had it in and checked it over, and found nothing wrong, they need to start replacing things I think, not just tighting up a few bolts. I have driven 4 other 400h, with less than 2,000 miles on, and they are OK, no viberations. To me it seems to be the part that engages when the engine cuts in, anyone know what that part may be called?? I have also asked Lexus UK for a letter to say that the car is built with a vibration if they try to say to me thats its normal to have this problem, some how that should concentrate their minds.
I do not have bad year tyres by the way.
My car is a Sept/2008 model with 1,500 miles on it

 

Thanks KIM.

Maybe it is the ICE (Internal Combined Engine).

I already called the customer satisfaction department of Lexus US headquarter last week, they have not told me it was normal yet, if they do, I will ask them to write me a letter as well.

If you have a case number please let me know, so, they can reference your case as well. I will try to get mine, I should have one.

Hope our 400h can be fixed soon.

 

I don't have this issue on my 400h but I had a similiar problem on my wifes car awhile back. I though about the tires but couldn't believe that that was the problem. I eventually put new tires on and was shocked when I drove it home and the problem was completely corrected. They weren't Goodyear tires.

I wouldn't exclude the tire possibility.

 

Haven't experienced this problem, but we had X-Ice 17"'s put on at delivery. Over 2000 miles, with no problems.

 

Your wife's car is a 400h as well?

 

Does the shaking occur continuously as you are lightly accelerating, or does the shaking occur once as you are increasing speed?
If the shaking thing occurs once during a mild acceleration, I would tend to think it is happening at the point the gas engine is starting. Feels like kind of a lurch. Mine does this on occasion and I know that it is perfectly normal for this to occur. You can monitor the power flow on the multi-display or instrument cluster to see the point the gas engine starts working, and feel the lurch happening at that time.

 

The gas pedal shakes constantly when the car is in low speed and the power meter is between 5-35 KW.

 

Please check this link for the vibration issue.
https://www.clublexus.com/forums/rx4...new-tires.html

 

well the car's going in tommorow, for a week, so I will let you know what the out come is. The after sales regioninal manager has driven my car and agrees the vibratation is worse than in the other 2 cars he drove the other day. He's talking about engine mounting plates maybe to tight, I told him that something needs replacing.....We shall see next week, if not they can have the car back and the fun will begin. I will mentioned the tyre issue to them as well. Will keep advised, cheers, Kim from across the pond

 

The 400h I test drove did this, one of the primary reasons I went with a 350. Other reasons were that we bought this vehicle for road trips, and the benefit of the electrical motors is dubious on highway mileage, so we didn't feel the need to spend extra cash. IMHO, a vehicle like this is supposed to be smooth.

 

Hi KIM,

Thanks for the update. Looking forward good news from you soon.

Cheers,
George

 

Our 400h doesn't experience this problem. We have almost 7,000 clicks on her. Great MPG, even on the highway!