I have a 1992 truck with 22re and 180k miles. They told me the engine is running perfect and to leave it alone as the chain will get noisy if it needs to be replaced and their mechanics can tell when it needs to be changed. What do you thing about NOT replacing the tc, per Toyota dealership?
I agree with the dealership. I also have a '92 22RE which ran fine up to 417,671 miles. Then one morning I heard an rather loud and worrisome marbles-in-a-tin-can sound from the engine that lasted 5-10 seconds. That sound was the timing chain running slack and slapping against the drivers side chain guide. The chain was running slack because the chain tensioner was getting lazy and failing to instantly tension the chain upon engine start up. So I stopped driving the truck until I had time to replace the timing chain mechanism. Because I stopped driving the truck right away, my plastic chain guides did not break into pieces and fall into the oil pan.
So the dealership is right - you'll hear a new a loud marbles-in-a-tin-can sound from the engine if your timing chain ever needs to be replaced. Original owners who change their oil alot and do alot highway driving get 300,000 -500,000 miles of life from the timing chain.
I replaced my chain mechanism with all Toyota parts (including new nylon plastic chain guides) because the factory parts already had a 417,671 mile track record of durability. And I'm now at 473,600 miles and no further problems.
Alot of owners have the mistaken impression that broken plastic chain guides causes the timing chain to rattle and that metal guides will prevent / cure the rattle. Wrong! A weak timing chain tensioner is what causes the chain rattle. So even with metal guides installed a chain can rattle. So it is critically important to replace your chain tensioner with the highest quality tensioner available - a Japan made Toyota brand tensioner. Most owners do the opposite - they buy a cheaply priced "made in the USA" timing kit with metal guides from partusa.com, enginebuilder.com etc., and end up with a cheap quality tensioner. So down the road they will need to change their timing chain mechanism again because their cheap quality tensioner will get lazy causing the chain to rub against their metal guides and grinding bits of rubber and metal off them which will circulate through the engine (not good). Maybe at that point they will begin to understand the metal guides are partly a marketing gimmick because they distract the owner from realizing how important it is to use a top quality factory tensioner.
Since I'm at 473,600 miles I also disagree with the owners here who said you need a new oil pump, rebuilt cylinder head, and so forth. Many of these owners are not original owners like you and I are - they bought well used and abused Toyotas for a low price and so alot of stuff on their engines is already worn out at only 100,000 - 200,000 miles.