Unless you're mechanically inclined, I suggest you take it to the dealer to do, or a mechanic/shop you trust.... not all that difficult but if done improperly, it can be a train wreck.

If you get the dealer to do it - expect the charges to run anywhere from 900 to 1400 dollars.

Here is a link to a DIY thread:

Tundra 4.7 (2uz) Timing Belt & Water Pump Replacement - YotaTech Forums

re.ac.tor

I had the timing belt and water pump changed at the same time since they were in there anyway at 110,000 first time. I went to a toyota dealership and they charged me little bit over $700.00. I now have 160,000 miles on my engine and its running great.

At 100K miles, it would be best to change your timing belt, fan belt, water pump, flush your radiator, service your transmission, and change your plugs. If your timing belt breaks it cause other issues to the internial workings of your engine, could easily bend your lifter rods which would be a major expense. The water pump usually will last at a minimum of 100,000 miles, but it will be less expensive to change them both at one time rather than to change separately. The same parts have to be removed to replace both.
I personally do not use the dealership, but you can purchase the parts and have a trusted mechanic perform the maintenance. I would estimate the service for the above would be between $1,000.00 and $1,500 based on the rates in my area. Look at it like a 100,000 mile maintenace and save a little at each paycheck to cover the cost.

I have put 107k on my 07 Tundra in the last two years and was wondering about the "maintenance schedual". I was told that our trucks have a timing chain, not belt, on the 5.7's. Truck of course doesn't seem as fast or strong as new so Im looking for suggestions. I'm in the middle of buying a house so go easy on me. Thanks.

KC have you done a plug change recently? Is it slugish or just wont get up and skoot? I would start with the easy stuff service tranny, plugs, fuel may be slightly contaminated, from your pic I see a 4 x 4 I don't know about the front ends but something is slowing it down/not as tight. maybe service front gear,lots of variables but you need to bring here back to new condition, (clean condition) but remember once you start replacing to stronger/newer the others parts will be in a sense weaker basically you need to zero time the replaceable power parts...just sayin

No I haven't done plug change or anything. One of the last oil changes I asked them to check the transmission oil, but they said they didn't know how!? It's not a 4x4, it's the TSS Toyota Sport Series with a 3" lift. It'll still scoot, just not as fast as it used to. I can tell a difference in power with just a fresh oil change. Thanks for the info. and I'll start with plug and wire change, fuel filters, etc.. I just left the dealership and forgot to ask about the 5.7s having the chain or belt. I'll repost later with that info. for those who are wondering about it too.

KCCHILDS,

The 5.7L does indeed have a timing chain. The chain will loosen a little as time goes by and I do not think Toyota has come out with a service interval for it.

re.ac.tor

Originally Posted by jdm

I'm pretty sure my timing belt has not been changed and I'm just over 100K. How big of a project is that going to be? 2002 V8

it can be a pain without air power....like an all day pain. with air power and the right tools i can knock out a t-belt and water pump on a V8 (no seals) in about 2hrs.

that being said, of all the t belts that ive replaced on tundras, i have never seen an old belt break from being ran too long (120xxx). ive also never seen a old V8 t belt with stretch marks/cracks ect.

i fully expect a v8 toyota timing belt can be saftly run to about 150,xxx miles.... now with this kinda mileage on the t/belt, your gaurenteed that the water pump will need replacement from a front seal leaking out