HtxRunner

Hey gang- longtime lurker here due to the tremendous wealth of knowledge everyone shares. I'm hoping you can give me a bit of advise.

I am currently looking at a 2003 GX470 with 110k on the clock. The car has great maintenance records for oil changes, but has yet to have the timing belt replaced. I understand the importance of this and if I decide to buy it would be replacing the water pump/timing belt right away, but I wanted to know if there's anything to be worried about now. Could a tired belt cause any problems that I should look out for, or the old water pump? Thanks for any insight you guys can share.

chiph9

The 2003 is a non-interference engine (no VVT-i) so the risk of catastrophic damage is low.
There is some debate over whether the older 2UZ-FE (non VVT-i) is an interference design. To be safe, don't delay on this work. Get the seller to lower their price (split the difference, whatever).

When you get this done, the labor is the expensive part. So you want to replace any/all parts in that region of the engine as you don't want to pay the labor twice. Timing belt. Idler. Seals. Thermostat. Water pump. Serpentine belt. And so on.

Chip H>

DiabloX22

Chip, where did you get that info????? The 03 IS a interference engine!!! BREAK BIG $!

DiabloX22

If the water pump wears, it is designed to leak or weep through the weep hole. Other problems can arise and make it go out. Yes a tired belt can cause huge damage, along with any other parts that run with the belt, as Chip did mention those other components. Did the owner tell you the timing belt wasn't done? Plus there is more maintenance on these than just oil changes. I also have a 03, we have non sealed transmissions vs the sealed, and along with other fluids and maint. items. If they serviced it at lexus, get the vin and go to lexus.com you can see the history of everything performed. Any questions, feel free to ask!

chiph9

There were a couple of threads on IH8MUD where the owners described spinning the crank without a timing belt installed and no hits were felt. It's possible that at high rpm there might be some hits though.

I'll edit my post just to be on the safe side.

Chip H.

DiabloX22

Chip, I was not being a AH, by no means! That is true, at low rpms a interference engine may not suffer damage if lucky, but being able to know when its going to break is impossible. Most timing belt manufactures websites will tell you if they are or aren't. But ours are, I would not want to have that happen to you or anyone from misunderstanding. I agree with you on getting ALL it done while in there, take no chances! I had customers skip rollers, seals, etc, and shred the belt trying to save a few bucks! Just like the seals, if they aren't leaking now, while in there, doesn't mean they wont start to, oil on a rubber belt, not good! Mine was done by a dealer before I owned it, however the description on lexus.com says "replaced timing belt" I wish it listed ALL the components, not just the belt. Common sense from a dealer doing the job, I would think EVERYTHING was done, but its still in the back of my mind.

Oldmanb777

If it hasn't broken, its extremely unlikely there is any damage to anything, YET! But get it done right away. As someone said, use that as a bargaining chip, split the cost. Or maybe the seller has already figured that in the price. Nice part of that not being done is, now you have a better opportunity to have all the maint brought up to date, and know it was done and when.

deeken

I recently got a 06 GX470 with 117k miles on it. The timing belts were never changed so the first thing I did before I even drove it home was take it to the Lexus dealership and get the timing belt and water pump replaced. It cost me about $900 for that. I ended up needing a new radiator as well since the old one was leaking so that cost me an extra $500. They wanted to sell me a OEM radiator for $900 + $300 installation but I told them no thanks. The support rep called me back a few hours later and said he could install an aftermarket Radiator for $500 and I said ok.It cost me about $1500 for everything but I now have piece of mind. I want this car to last me another 100k miles.

chiph9

Next time ease me into it. lol.

Some people are just lucky - I have a friend who had a 1st gen DSM Eclipse GSX whose timing belt broke while he was driving. It's definitely an interference engine, but somehow he got away without anything being bent. Wouldn't happen to me.

Chip H.