1999 4Runner Rumble (55+ MPH)

So, I bought a stock 1999 4Runner (currently 234k miles) from a friend back in 2018-2019 and I have noticed a vibration when driving 55+ mph. It sounds kind of like I'm driving on rumble strips. It gets worse when I let off the gas and always stops when I get under ~55 mph.

I am not very well educated on all things car so I have no idea where to start looking.

 

Welcome to the forum, I’m going to start off with u-joints, but do you know what the maintenance on it has been, or not been done?

 

My dad said that the u-joints aren't loose or anything. I'd have to look into the book about maintenance.

 

At 234k there are so many things that need attention if they have not been done, it can seem overwhelming, but start on the things that can be catastrophic such as the lbj’s (lower ball joints), and it is pretty much a givin that all the suspension needs looked at. I’m sure others will chime in soon.

 

I would take it to a professional for tires and inspection first. They can diagnose it and suggest improvements...,,An out of balance tire,,yes,, they need to be rotated every five thousand miles...,and ,can be very annoying..,,,

 

Sounds like what happened to my brother-in-law...,,, Ford installed a new wheel bearing on a fairly new Explorer when he left and got on the highway the tire started vibrating and the whole wheel fell off and rolled down the road....

 

Yeah, I vote for a good suspension shop/mechanic to look it over.

Do you feel this vibration in the steering wheel? Do you feel it riding in the back of the car? Do you get the vibration in the brake pedal?

For something like that, typical culprits I can think of in order from the most likely:

Tire or Tires out of balance. - rotate fronts to back. If there is a change...you need balancing or new rims\tires.
Rim is bent - same as tires.
Brake Discs are warped. - usually starts as a pulsing in the brake pedal...but can cause a vibration.
UJoints - loose drive shaft can cause a vibration. Usually you get clunks when you engage the transmission from drive to reverse.
Ball Joints and suspension bushings are shot - Have a shop check these out.
Bad Wheel Bearing - Usually this is a whine and not a vibration...but when they are about to let the wheel escape...they can vibrate.
Bad drive shaft? - Someone mentioned a bad drive shaft causes weird vibrations in 2 of his 4 runners because the OEM shaft has a rubber insert that goes bad...I have heard this in old Mustangs as well. Very last thing to check.

 

OK, my recently acquired '00 4runner with 240k miles has developed a new vibration issue. at low speed, under 30, it almost feels like a dead miss, smooths out between 30 and 55 or so, then comes back worse between 55 and up. But anytime its vibrating, if i let off the gas it stops, and its in the seat, not the steering wheel (so no front end suspension/tire prob, I think) and not in the brake pedal (so no brake probs either). The check engine light has been on for years (evap cannister, yeah, I know, on my list to get fixed, lol), but when this is happening the ck engine light starts flashing on and off. I helped maintain the vehicle for the last 10 yrs, as in offered advice when probs cropped up, and took to shop for probs when requested. I don't know that rear end lube level ever checked (at least I never specifically told the shop to do it, may have been ck'd as some regular inspection). Getting codes pulled this afternoon. Looking for options, opinions and best guesses. I'm betting drive shaft or rear end.

 

Great list! Happened to me on my then new to me 4runner. I suspected tires but turned out to be brakes. Tell tale sign is there is no vibration until it heats up. I was very happy it was brakes (considered maintenance) rather than suspension at my low miles.