2UZ Timing Belt at 20 years and 135k

[Rednexus]

I helped a buddy change the original timing belt in his 2002 Tundra a couple of weeks ago, and found the old belt laying in my shop still today. Based on the inspection of this belt, despite it only being 30% over the mileage limit, it was NOT in good shape. There were a couple of places where the fibers were starting to rip in the belt. It was also pretty loose before we removed it, and the engine ran noticeable better after the new Aisin kit went on. I attribute this to sloppy/wandering cam timing due to a loose belt.

Interestingly enough, I had gone with him to look at this truck at the dealer. We brought up the fact of it needing a belt and the dealer was insistent that he had had these go to 170K on his personal 2UZ's. After looking at this belt, I'm not sure it had much more life in it at all. A few high-revving events might have further deteriorated it and caused it to break.

So...the moral of the story is...despite low mileage, please change your timing belts! Age seemingly affects them just as much.

 

[jiggletits]

I'd be more concerned with age than mileage, but it should have been changed at 90k.

I have a 27k original mile 1986 MR2 that has never had the belt change. 36 years old. Just waiting for it to pop. Not a car I rely on.

 

[GrizzlyClint]

I helped a buddy change the original timing belt in his 2002 Tundra a couple of weeks ago, and found the old belt laying in my shop still today. Based on the inspection of this belt, despite it only being 30% over the mileage limit, it was NOT in good shape. There were a couple of places where the fibers were starting to rip in the belt. It was also pretty loose before we removed it, and the engine ran noticeable better after the new Aisin kit went on. I attribute this to sloppy/wandering cam timing due to a loose belt.

Interestingly enough, I had gone with him to look at this truck at the dealer. We brought up the fact of it needing a belt and the dealer was insistent that he had had these go to 170K on his personal 2UZ's. After looking at this belt, I'm not sure it had much more life in it at all. A few high-revving events might have further deteriorated it and caused it to break.

So...the moral of the story is...despite low mileage, please change your timing belts! Age seemingly affects them just as much.

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^ 100%

I ALWAYS tell people rubber and plastic still age regardless of miles. So any low mileage vehicle 8+ years or older will have aged plastic and rubber. The engine bay heat under the bonnet will accelerate this as well.

 

[Rednexus]

^ 100%

I ALWAYS tell people rubber and plastic still age regardless of miles. So any low mileage vehicle 8+ years or older will have aged plastic and rubber. The engine bay heat under the bonnet will accelerate this as well.

The biggest thing for me was how much the belt and stretched and how much better the Tundra ran after it was replaced. It was loose! Any rubber that is under constant tension for 20 years is going to creep and stretch. This probably also put it at risk for skipping a tooth.

We also replaced many of his coolant and heater hoses, but the OEM hoses were still in great shape! I replaced several in my GX at 13 years and found the same thing. Toyota must use excellent quality rubber in their cooling system hoses.

 

[gnob]

Definitely have seen 5vz @200k+ on og belt.
These new belts are much more reliable than when they first came out.

Id personally be a bit worry some about that 40yo mr2 belt. Lol

 

[Rednexus]

Definitely have seen 5vz @200k+ on og belt.
These new belts are much more reliable than when they first came out.

Id personally be a bit worry some about that 40yo mr2 belt. Lol

I still like belt engines more than chain engines. They are quieter, smoother, simpler, and seem to rev a lot faster. Timing chain problems can also be pretty gruesome and send a lot of metal and plastic guide debris through an engine. I understand that most manufacturers switched to chains to remove a "maintenance" item, but a few T-belt changes is really NBD over a vehicle's lifespan.

 

[GrizzlyClint]

Toyota must use excellent quality rubber in their cooling system hoses.

They do. Before I sold my ‘08 470 with almost 183k the original factory hoses were still in great shape I would of replaced them at 190k when my timing/water pump service would of been done. I replaced my ‘10 460’s hoses at ~147k. They were a bit more worn.

 

[jiggletits]

There are many reasons to only use Toyota OE parts. You get what you pay for and they are always the highest quality.

 

[GrizzlyClint]

There are many reasons to only use Toyota OE parts. You get what you pay for and they are always the highest quality.

100%.