N3doomed

I have 2004 LS 430. The timing belt was changed in 2014(10 years ago) but has only put on 30k miles since then. I've checked the belt out through the timing cover on right side. The belt looks brand new with no signs of wear. My question is should I be worried about other components? I would say the idlers and water pump should go by mileage not time. How about the tensioner?

weldthedif

unless you're hearing bearings squealing or coolant seeping from the water pump, you're probably safe to push it another few years.
Mine was done 10 years ago as well, and mileage wise its not due for another 20-30k, but I am doing it this (winter24-25) as peace of mind. I pushed it off 2 years already

NAiL05

It would need to be replaced time wise since usually it's 6 years on the v8's as I recall. I do know they extended the v6 timing belt time intervals. Optional to do the tensioners and idlers depending on mileage wise. I usually just do them second timing belt change even though from my inspection on both my cars it does not need it. The belt can look physically in good shape but over time rubber fails and stretches after heat cycling so many times. Can you get away with not doing one for 10 years with rarely driving the car? Yes. Can it go for longer? Possibly...but after the recommended time interval it is a guess. Just remember cheaper to replace a timing belt than an engine if something does happen to go wrong even if there is barely any mileage on it.

SAATR

I'll say that there is a reason that belt change intervals are rated by BOTH time-in-service and mileage. Simple exposure to oxygen, ozone, and other gasses found in the atmosphere will break down the chemistry of a belt with no use at all. Would you purchase and install a years-old belt simply because it has no use or mileage? Likely not. I know Toyota's change intervals seem conservative compared to the service life these belts and components have actually been pushed to, but it's always a risk going beyond engineered usage, no matter how well calculated.

The tensioner, tensioner pulley, and pump SHOULD be changed as a system, along with the belt. My own car definitely had a belt swap rather than a complete system change during the previous ownership, and the pump was seeping from the weep hole, along with having a slight grittiness in the bearings of the pulleys. A failure in any of these will kill the engine, so the cost/benefit of reuse simply isn't there, at least for me. A few hundred extra to do the complete job which is then good for another decade of service is an easy decision.

Tmaxxexpress

I just purchased 2004 flavor. Has 224,000 miles. The belt looked ok as a visual. I put it beside my new one and the old one was about 1/8 longer than the new one. Also I would line up the crank mark on the old belt. The 2 cam marks would be off like a 1/16 of inch. The tensioner had a small wobble. Not audible. The puppy on driver side had slight scoring. So, even though a visual inspection through the dam cover would say. Let us ok it was not ok. The car was running great with the old valet but it wasn’t gonn a be long.

Bocatrip

After about 18 years on this forum, I don’t hear much on timing belts failing. I’m sure they do, but they are quite robust. I’m am guilty at neglecting my belt replacement. I purchased my car 16+ years ago when the first belt replacement was done by previous owner at around 95,000 miles. I’m currently at 172,000 miles with that belt as well as the original water pump. I am planning on taking a look at the belt’s condition and make a replacement decision then. I’ll keep my fingers crossed. I’ve been looking for a lower mileage LS430 with no luck for years.

Freddy12

At the end of the day, I'll opt for peace of mind: engine vs belt? You choose but I know my choice, sleep is good.

Bocatrip

. I totally understand.

N3doomed

Thanks all for your replies. I am setting up a time in next week to do it. Even though it will probably last I can't deal with the gamble!