My 1987 Toyota 4Runner has a wacking noise (for lack of a better description!) from (it sounds like) the left front end, that starts at about 40 mph and increases as the vehicle speeds up. I've checked for something wrapped up in the drive shaft and axles, but can't find anything...help!
In regards to your 1987 Toyota 4Runner, if you are hearing a noise from the left front end, at a speed of 40 mph and higher it might be a possible wheel bearing. This is usually the most common type of repair based on the description.
If you need help finding a local technician, please find an AskPatty Certified Repair Shop at http://www.askpatty.com/search/?type=all&m=30&q=&keyword= and they can help you diagnose and repair the problem.
〉 Answered on Feb 9th, 2016 by Maryann Croce, Owner at Croce’s Transmission Specialists
If the sound slows down or speeds up as you decrease or increase the vehicle's speed, you could have a small rock or other item wedged into the tire treads, and that could be contributing to the sound. Your tire might even have a screw or nail embedded in the rubber. If you aren't able to find it on the tire through a visual examination, you might want to take it to your local tire shop for their evaluation.
I suggest you inspect your strut mounts. They may be worn and causing a bumping/grinding noise. This sound like a front end issue, considering the age. If your tires are wearing unevenly this is a sure indication of excessive front end play.