ticking noise underneath the car

[lilm]

is it really loud enough to bother you..... i mean do you just sit by your car listning to it............just walk away

[PhreakdOut]

Oil dripping back into the oilpan? I don't think so. Ever dripped oil into a drain pan that already has oil in it? Pretty quiet. Add on the fact the the oil pan is of dense material to withstand occasional impacts. If your oil is dripping into an empty oil pan, you have more problems than ticking.

The ticking you hear IS the exhaust system. The issue is thermal expansion of metal.

Just after the catalytic converter resides a bullet shaped resonator that Toyota calls a submuffler. The submuffler typically has a straight through innerpipe made of perforated material formed into a tube at a thickness of 1.2mm. The shell of the submuffler is a much larger diameter tube (usually around 120mm) and has a material thickness of 1.5mm.

The innerpipe, being of thinner material and closer to the source of heat will expand first. (Side note, all exhaust systems grow in length during full operation and shrink back down after cooling. This is normal and controlled.) To keep the innerpipe from failing due to thermal fatigue, only the inlet end is welded to the upstream pipe. The outlet end will have a wiremesh ring to allow the mating pipe to slide a few millimeters during thermal expansion and contraction. Older mid 80's Honda Civics had it bad because they would weld both ends of the innerpipe and this would result in a loud "ping" during cool down. Toyota has spared you that irritation.

While the whole system ticks as each section of pipe contracts, most noise is heard from the submuffler outershell. The second most likely source of noice comes from converter heatshields. The shields on the front converters at the manifold are typically bolted on and do not have provisions for expansion. This is the reason they are bolted and not welded. Thermal expansion would fracture one or more welds. Bolts are stronger in this situation.

There's no fix for it. It's natural. Nothing is going to break and it's common to all cars.

[lilm]

hey phreakd whats the "submuffler" for....noise reduction?

[i3oostedcubes]

It's just an annoyance and I don't think it's normal to expect a ticking noise like the chinese water torture it is.

Toyota spends so much time engineering, materials, money on keeping the car quiet yet they let the exhaust ping away? All my other cars don't do this and quality wasn't their upmost aspect hehe. I'll find a way, if I have to replace the whole exhaust with my custom made pipes I will.

[QuickSEV6]

I once heard a ticking sound coming from underneath my car. When I searched for the source, I found an alarm clock attatched to 5 sticks of dynamite. I clipped the wires and I am now on the federal witness protection program.

LOL