2003 Toyota Tacoma Making Noises It Shouldn't

I have a 2003 Toyota Tacoma 4 cylinder manual transmission, regular cab. I have noticed in the last few weeks that it is getting louder. The noise seems to be coming from the behind the seats under the truck not the engine. The noise increases when you speed up. And makes less noise when you slow down or let your foot off the gas pedal. There seems to be something loose and it occasionally sounds like chains rattling from that area. I’m not experiencing any performance loss and besides the noise the truck runs fine. I took the truck in today to have the oil changed and see if they would check it out. i took the truck to my truck to the toyota dealership where I purchased it. My first thought it was the muffler so I asked them to check it, but they said that was fine. They had someone drive it and told me I need to bring it back in. They said it might be a rear differential or the transmission problem and needed more time with it.

What do you think? Any suggestions? How much could this cost?


I’d take it to a reputable independent shop. If it sounds like chains rattling, it could be as simple as needing a new set of plugs…it could be pinging. Or it could be a faulty EGR system or knock sensor, as they prevent pinging. Or it could even be a rattling heat shield on the cat converter.

There are a whole bunch or possibilities. I’m skeptical of their statement. Is the Check Engine Light lit?

No the check light engine has not come on.

That would suggest that the problem is other than an engine operating problem, but I’d still be suspicious of a statement like theirs without some supporting diagnostic data. Having said that, they did tell you they needed more time with it and may have been simply preparing you for the worst possible scenerio. It’s hard to tell from here.

Sometimes the jack crank rattles behind the seat. If it is there.