Hi all,
I'm new to this forum and had some general questions re: my 1994 SC400 that has 307,000 miles (schedule B conditions) on it. I was looking up the maintenance schedule and couldn't find anything specific on when to change the timing belt, AT fluids or differential fluids. I have been changing the belt about every 100K miles. What do you all think? Also do you usually also change all the drive belts, seals including water pump at the same time as my (non-dealer) mechanic recommends? I also use 5-30 oil as recommended by the factory with very little leakage. Any opinions on viscosity with this hi-mileage engine?

What is the most mileage people have seen with this engine? Mine is mostly freeway miles.

Thanks in advance for any advice.

 

im not sure on the schedule intervals but i love to see a sc with this many miles any pics?

 

timing belt and water pump every 90k

check out this thread for mileage https://www.clublexus.com/forums/sho...ighest+mileage

What kind of gas mileage do you get?

 

Mostly freeway (90%) gets me about 22mi/gallon.

More if I keep under the speed limit.

 

Will post when I clean it up a bit.

Thanks.

 

307,000 miles "that's incredable"...what a great car!

 

 

Dang, that's a lot of miles... Since the timing belt and waterpump are in the same region, i usually replace those at the same time since it takes a lot of time to change the timing belt and water pump... I'm not to sure about the SC nor the GS, but generally this is the rule of thumb...

 

Is that on the original motor?

 

if you're changing the water pump, change the timing belt as well, as you have to remove it to get the water pump out...

100k is not too late to change your timing belt on a 1UZ if you're not leaking any oil... but at 100k, change EVERYTHING... water pump, timing belt, idler and tensioner bearings, cam and crank seals, serpentine belt, dizzy caps, rotors, plugs, wires...

 

OK you said the car has 307,000 miles but the mileage indicator says 621,382? Did you get a new engine in between, maybe a rebuild?

 

2 different people posted that... lem321 has 307, o.l.t. posted 621

 

At that milage I would drain/refill the ATF, and replace the timing belt and water pump. If you want to stop those leaks switch over to a 5W-30 for high mileage vehicles, they have additives that will swell up the seals and stop the leak in 1-3 oil changes.

Toyota sure can make a reliable car.

 

My friend's mom drives a 425k mile 4runner. She is not going to ever sell that car.

 

Since I posted as the original poster, I now have 458K miles and the SC400 finally died. Probably oil from a leaky valve cover got into the plugs so one bank on the driver's side is not firing. The radiator also sprung a leak. Decided to not invest any more into the old girl. Just purchased a "new" 2000 SC400 in Millenium Silver that only has 112K miles and relatively speaking, it looks new. These are really great cars!