rkorts

I am considering buy a 1993 SC-300, it has 117,000 miles.

The seller knows nothing about the timing belt (used car dealer). How many miles should this vehicle have to REQUIRE a new timing belt?

scsexy

iTrader: (1)

This is something only a visual inspection can tell you. You can pop the little cover off the belt with a 6mm allen tool and check out the condition of the belt. If its frayed or cracked at all you should replace it now.
If it looks great, keep an eye on it and do it soon because you are past the recommended replacement of 90,000 miles or 10 years.

KahnBB6

iTrader: (5)

Technically for 1992-1997 SC300's the timing belt, spark plugs (use the correct model Denso or NGK plugs), Denso plug leads, Denso/Toyota cap and and Denso/Toyota rotor are all due every 60k miles. This is going by the original service schedule recommendations in the owner's manual.

It's also a good idea to install a new water pump when changing a timing belt that's pretty old just because it's very easy to do while you're in there. In addition just due to the age of the vehicle this is also a good time to carefully inspect the OEM harmonic balancer (crank pulley) and if there is any early sign of separation or cracking of the dampening rubber built into it this is also a good time to replace that as well if you're otherwise going to leave a brand new timing belt alone for another 60k miles.

For 1998-2005 2JZ-GE VVT-i engine equipped Toyota/Lexus vehicles I do believe it jumped to 90k miles for some reason. I'm not sure why honestly.

Nonetheless if you have no records of the last timing belt service and a quick check of the service history based on the SC300's VIN number at a local dealer (or on the main Lexus website owner's section) cannot tell you this then just plan on getting these services done if you purchase the vehicle.

All in all a 117k mile SC300 is considered (by the CL community at least) to be low mileage these days. Nice find!

1997Soarer

iTrader: (1)

The 90k jump was from corporate. The jump happened when maintenance schedules across the board were altered and extended. For some engines, the lengthen schedule didn't hurt anything. But for others, it was catastrophic. This bean-counter change is why the now famous 5S and 1MZ sludging issues started, as the conventional oil change interval jumped from 3k to 5k (which was now the same as syn oil).

The JZ and UZ motors were really stout and weren't hurt by the change. With the upgrade in tech that was introduced with VVTI and factory iridium plugs, there were less wear parts (no more distributors, coilpacks + shorter plug wires).

1997Soarer

iTrader: (1)

If this SC300 has only 117k on it, and this is the first or second owner, then the timing belt and water pump has never been done.
Which means it is way past due.

KahnBB6

iTrader: (5)

^^ Thank you for clearing that up Brian! The jump from every 60k to every 90k for the belt and plugs was always baffling to me since the basic engine designs remained the same apart from the addition of VVT-i and lightening the rotating assemblies a bit. I did not know that other Toyota and Lexus models not having a JZ or UZ engine were so affected by this change across the board.

OP, I agree with him. For a 1993 SC300 with the 60k timing belt intervals I suspect one full belt service was performed during the car's service life but the second belt service will be due right about now especially given the age and years on it.

I recommend sticking with all Toyota OEM or Denso parts for this. The water pump may be the original one the car was manufactured with and so I would replace that too at the same time while you're in there. Same with using the OEM Denso Iridium spark plugs, new Denso/OEM plug wires, Denso/OEM cap and Denso/OEM rotor.

joewitafro

Bought my 95' SC with 139k with the original timing belt/water pump and I haven't had the time or cash to replace it yet, at 142k now. If this was a vvt-i motor the risk of breaking a timing belt is a lot more catastrophic being interference. But for non vvt-i a belt snap isn't going to cost me a motor, just a tow. I will probably have it done this year though by 145k.

perfctreig

FWIW, my 1993 SC400 has 237,000 miles and never had the timing belt changed. Granted it is a non interference engine, but still....

1997Soarer

iTrader: (1)

What's interesting is that the maintenance schedule for the Toyota Supra was not changed. Supra 2JZGE and 2JZGTE kept the same 60k belt schedule as before.

KahnBB6

iTrader: (5)

That is interesting. What year did this change go into effect? For the U.S. and Canada in 1998 only the Supra NA got the VVT-i engine while the Turbo engine was a carryover unchanged from '97 but now excluding sales in California. This sounds like Toyota rightly assumed that their flagship sportscar in both NA and Turbo trim levels would see more hard use than their luxury vehicles using the same NA engine.

Bimmerbill

What about the Gates blue belt with carbon fiber intended for racing or street. Is this over the top for a street driven car?

1997Soarer

iTrader: (1)

Yup, that's basically what I came up with while I was working for Toyota. Everything switched in 98 but they didn't apply the change to the Supra. I assume either they expected the cars to be driven, or accountants /PR crunched numbers and decided that the halo car was not the sort of car to cheap out on