JBrady

Anyone know for CERTAIN whether the Lexus V8 is an interference engine, IE, do the pistons hit the valves if the timing belts snaps? All years the same? Thanks.

fire

95 and newer V8's ARE interference motors. 90-94 are not. Timing belt replacement changed to 90k from 120k in 95 as I understand it.

Lex Luthor

Who told you Lexus says 120k for the timing belt?

Bean

iTrader: (1)

and i don't think ANY 1uz is interference; they aren't going to change the design midway through

Lex Luthor

Correct.

Bean

iTrader: (1)

So let it be known that this statement: "95 and newer V8's ARE interference motors. 90-94 are not. " from fire is incorrect.

the 1uz and 2jz are both noninterference motors throughout their entire existence

quick

Got any proof?

SC300T

Ummmm... no proof, but my Lexus tech has told us that nothing will happen if the timing belt snaps on our 99 GS400, 92 SC300 or 93 LS400 (no longer have the LS).

I'm at the dealer quite a bit talking to the techs and what not. Never seen an engine pulled for a bent valve. Oddly enough I always seem to see RX300s with engines pulled for worn cylinder bores...

I personally wouldn't replace a timing belt before 100k miles (unless the water pump fails) on these. They just don't break enough.

JBrady

Guys,

Thanks for the imput. Problem is everyone is going on someone elses imformation. Lexus owners are for the most part NOT high rpm people. They, for the most part, are scheduled maintenance types. This means very few cars will ever get to the point of failure. Just because something doesn't fail doesn't mean it will not. I have seen tires on cars that are thread worn NOT fail and seen nearly new tires fail!!! Sometimes, usually, don't worry about it are like any accident... never happens until it does

I am VERY surprised at ANY high compression engine that will not hit valves during a cam drive failure. This means that any valve can be held completely open and have the piston NOT hit it as it passes TDC. Very unusual. I did have a low compression (8 to 1) turbo motor with dished pistons that was non-interference but that, as I said, is unusual. SO, understandably I am sceptical. I have had MANY experts tell me INCORRECT information.

My 96 LS400 is approaching 90k miles. It is warrantied to 100k. If I do not do the service and something fails it is my cost. I know it is only 10k miles but I do want the belt replaced within no more than 20k (yes I intend to keep the car) so, I will probably have it done and have peace of mind. I would LOVE to see an actual technical page or bulletin from Toyota on this question. Any guesses as to where to look?

Hermosa

I just saw in a tech manual today that at least the early SC400s are interference.

2Lexus430s

Not all high Comp engined vehicles are interference.

I had a 95 Nissan 300ZX TT and the 90-96 are all non-interference, they are free spinning, and that cars has a very high compression.