djamps

'98 LS400, 200k miles. Done it since I bought ~195k miles it and it hasn't changed. Cold start there is no noise, only after warmed up. Car runs really strong either way. Audibly annoying more than anything else.

Audio of slow revs in my garage:

MP3 AUDIO CLIP

alien1974

mine does this too 100k on the clock, i thought it could be the water pump, but as i am not losing water i am not worried

1uzLexzeus

Well I'm no mechanic, but my first guess is that it might be the whirring of the fan or belts . We've had an 02 tundra that does in my family since 09 and its been runnin like a champ since. Although it is currently in the shop for (timing belts and water pump).

RA40

iTrader: (6)

What specific sound are we listening for? Seems pretty normal with the drive belt whirring, pulleys and fan spinning.

djamps

It's a whirring sound that follows the RPMs, especially noticeable between 1k and 1.5k RPM. Less at idle. Only makes the noise when the engine is warmed up. Seems pulley/bearing-ish to me. I figured a LS400/1UZ veteran might know what it is.

djamps

FYI I haven't ran without the drivebelt, but I did replace the belt and the PS pump (due to leaking) but the noise didn't change at all.

KJG92

Transmission maybe?

djamps

So I'm really leaning towards the water pump. The intensity of the sound is practically identical to the temp gauge -- basically the amount of water flow. Getting the timing belt and water pump swapped soon, so we shall see.

alien1974

mine does it on tick over

cobalt91

Maybe the fan clutch has gone bad?

Nishy

no.... it's not whirring or ticking...




for real though, I have no idea

djamps

Thanks for the hints everyone, I'll slowly be tinkering with things over time -- main thing being the timing belt, pulleys and pump.

once I find the culprit I'll let you all know.