A mind-boggling vibration

toyota
4runner
vibration

#1

Hello Car Talk community,

I have had quite a puzzling affliction to my vehicle that no one can quite figure out. As a fan of the show, I thought that I would pose the problem to you in the event that you may be able to offer some advice. I truly don?t know what else to do.

I drive a 2000 Toyota 4-runner with approximately 140k miles. I love this truck. I use it for my work as a biologist and, despite the fact that it does not have 4-wheel drive, it is quite functional for many of the tasks that I perform. The two issues that I have are: one, I pretty much need a 4X4, and two, it has some major highway issues. Assuming that you cannot tell me a realistic way to convert it to 4-wheel drive, I’d like to focus on the highway issue.

This V6 truck accelerates fine up until around 65mph. At that moment is when the dreaded vibration starts. The vibration feels like the car is going to shake apart, but if I get the courage to speed up, then I notice that the vibration begins to subside at around 73mph. Getting up to that speed is made more difficult because the truck does not have as much acceleration after 65mph. This also makes maintaining 74mph much more difficult. The whole situation is extremely aggravating as I am in the car a ton, but essentially have to make arrangements when I know that I am going to be a longer trip, which is common these days.

This problem began around 5 years ago, and that is when I began asking mechanics to fix it. I have had the tires, plugs and wires replaced, the front end aligned, and the tires rotated and balanced twice (not all at the same time). Each time I go in, I explain my problem clearly, and each time I leave, am presented a large bill and assured that it’s fixed. It never is. I grew up in my Grandpa’s shop in Kansas City and tried to bring my Family’s full and extensive knowledge of cars to bear on the problem. This has not resulted in anything but the narrowing down of some aspects. First, the vibration seems to stay constant when I put my car in neutral at 70mph. It does not intensify with the RPMs. It feels like it is coming from the entire car, with the steering wheel vibrating the most noticeably. All of these seem to be helpful, but no one can seem to pinpoint the problem. For someone who considers himself pretty good with a wrench, this little ailment has caused a huge pain in the neck for me. So I’d love to hear your advice if you’ve got the time. I certainly appreciate any suggestions that you may be able to impart.

Take Care,

Lance


#2

Tires. Check for pressure, wear and wheel balance.


#3

I’ve completely replaced the tires twice. Each time I replaced them, they were balanced. I’ve also aligned the fron end twice, both times getting my wheels and tires balanced and rotated.


#4

Could be that you some how lost 1 or more balance weights from your drive shaft.It could be a transmission problem try accelerating through the 65-74 range with out the overdrive on. if there are no problems it could be a trans issue. I would also be a little worried that you have no acceleration above 65 and that it is difficult to maintain 74 with a V-6, something is wrong there. Might be related to to other problems ie. trans. Just a thought.


#5

I’ll look at those options and get back to you. Thanks for the new ideas.


#6

Check the drive shaft- my 97 has a 2 piece shaft that has some sort of slip fit. Mine was vibrating and I sprayed some lube in the slip joint and it went away.