RegCabTaco

I have a 96 (4cyl, 4x4) standard cab Tacoma and am having a difficult time determining what noise I am hearing. When accelerating I don't hear any unusual noise, but hear a grinding (metal on metal scraping type noise) when decelerating in a specific speed range (from about 25-30). However, I can't seem to tell where the noise is coming from. Its not very loud because you can't hear it with the windows up, but is very noticeable with the windows down. There isn't any excessive driveline vibes (more than normal). The noise doesn't get any worse when turning or going over any bumps. It just seems to be present in that specific speed range only while decelerating.

I lubed up the drive shaft and that didn't make a difference (excessively!).

I changed the rear diff fluid to see if there were metal pieces to see if there was a noticeable problem in the diff. I drained the oil and it looked very clean. However, there was a pasty substance on the magnet which was a mixture of sand like metal shaving and oil. However, I had my truck regeared a year and a half ago and Ive heard that is common as the gears break in.

Lately ive noticed a distinct smell around the driver side rear tire that smells like oil or brakes. However, after excessively lubing up the driveline it splattered some grease around the rear of the truck which may be the source of the smell from the truck parts heating up.

Could something in the drums be causing this noise or possibly the ebrake being an issue. I believe the smell in the rear of the truck smell more like brakes than oil.

Since I am unable to tell where the noise is coming from I'm about ready to take it to the dealer and see what they can come up with. Please help me avoid that! thanks for the help guys. Throw out whatever ideas might be responsible for hearing this high pitched noise.... It sounds a lot like using a grinder on metal.

MODZILLA

I'm thinkin it's a brake issue. Can you jack it up and pull the drum off? If you aren't very mechanically inclined i would urge you to take it to midas or someplace similar.

RegCabTaco

I sure can... That is what I am going to do tomorrow, but wanted to know what to look for. I am fairly mechanically inclined, but have never taken the drums off (this is my first vehicle). I think I should have no problem doing so, but wanted to know what to look for. Ive put on a header, changed the rack bushings, changed the front pads, repaired a hub... So I have a little experience working on my tacoma.

I would be really happy if that infact is the problem. I would hate to hear I'm having rear differential problems after having it regeared.

Thanks for the quick reply!

MODZILLA

well if there's a problem in there it should be obvious. A good repair manual is often the most important tool to have available. Metal on metal means there will be chunks-o-scheisse in there. If your e-brake linkage got dried up and seized you'll want some good spray lube and soak all the hinging points. Then free it up and work it several times. Once that's done I would grease all the hinge points outside the drum and avoid leaving any lube inside the drum. Wouldn't want any lube finding its way onto the brake shoes.

RegCabTaco

Alright... I'll do that tomorrow and see what happens. Thanks again.

MODZILLA

any time, let us know what you find.

RegCabTaco

WELL... the rear brakes seem to be fine! I cleaned them up with brake cleaner and it seemed to stop the burning smell ive been noticing. However, I now am noticing the damn grinding/rubbing noise at SLOWER SPEEDS! I think I am going to take it to the dealer tomorrow and see what they have to say. I probably wont have them do the work, but will let the "diagnose" the problem. Ive been trying to figure out where the noise is coming from for the past week and am getting NO WHERE!

mchombuilders

what does it do in 4hi/4lo ? just curious. My taco started making the same noises, but they sounded like they were coming from the tcase. In 4lo I hear an explosive ping as I seem to skip a tooth. aww sh!#. I had a close friend drive it up his dway while i rode the creeper (kids don't try this at home) hanging from the bumper. turns out its up front, but Im not sure if its the pinion or add sleeve. Anybody out there have a clue? good luck to you too, ooo.

Jboy

Any outcome after a dealer visit? I have the same noise between 10 and 15mph with the foot off the pedal.

wmunsell

I have a very similar if not the same problem. Through a ton of searching I came across a a forum that said it was a loos exhaust bracket that connects to your tranny. And when the engine reaches a specific RPM the vibration sounds like grinding. I personally have not had a chance yet to check this on my truck. I know in my situation, i only get the sound when my engine is hot and I take my foot off the gas. This grinding sound is greatly increased if a load is put on my truck, such as pulling a boat for a couple miles. The sound for me sounds like someone is putting a hand grinder on my exhaust heat shield. Kind of hard to explain but it's definitely not a thick metal grinding sound but more of a thin metal grinding sound. Ill keep you posted if I find it to be something else.

wmunsell

Holly $h1t I didn't see how old this post was!!