Unknown engine noise

uabericm · #1 (**permalink**) 09-26-2008, 12:10 PM

I just got back from a trip and decided to take the bride out to dinner. We took her 4runner and as we were leaving I notice a new noise. It sounds like an electric drill that speeds up with acceleration. It doesn't seem to affect the power of the engine or anything else.

Thoughts?

uabericm · #2 (**permalink**) 09-26-2008, 06:12 PM

I think it is coming from the front of the engine and possibly the passenger side.

davidnraleigh · #3 (**permalink**) 10-27-2008, 03:49 PM

Have your shop check out the rear differential closely. We have had a similar noise going on for months. Had our shop check it out and even had them replace perfectly good tires with new Michelins to no avail. They said w/o spending $100s just to check it out they couldn't figure out what the noise was. Didn't hear the noise while in reverse. Took it in to a dealer and they found that the RR axle seal was busted and the LR seal was seeping causing the differential to lose fluid and has been running dry for a while. $1,678 for the rear differential w/ carrier assembly and $821 for both axle seals.