Tundra Maintenance

commodore1

I don't have my Tundra yet, but I would like to
know something about routine maintenance. I would
like to know if the Tundra v8 has a timing belt or
a timing chain

bud_light_dude

Don't quote me on this, but I think all makes have abandoned the timing belts, and most of them have abandoned the timimg chain too. I believe they use a timing "gear".

Again, I am guessing, but wanted to give my opinion anyway. Have you asked the Tundra group over in the Tundra topics yet?

I would call a Toyota shop and ask to speak with one of the Master Tech's. They have alway's been really knowledgeable about the Toyota's I have had.

rs_petty

Needs replacing at 90k or so says my owners manual.

bud_light_dude

but I can't believe that Toyota is still using a timing beltstill today. Thats pretty cheesy! Timing beltsare very easily stretched. Even the chains are easily stretched.

commodore1

Thanks for the replies guys.. I would like to have seen timing gears on this high tech motor.

thanks again

pyrodex

but I can't believe someone brave enough to buy a Chevy would be concerned about whether a vehicle has a timing belt or not. If you can live with trannies falling apart and brake systems failing(among other things), why are you worried about a timing belt??!!

commodore,
rs petty is correct. Toyota recommends a 90k mile replacement for the timing belt.

Oil changes take a little over 7 quarts(I think it's 7.2 quarts) of oil if you're interested.

tgr1

Some manufacturers like belts because they run quieter than chains. A selling point to some people. Belts don't bother me, unless the valves don't clear the pistons. I had a belt break on a Honda, and it was bent valve city. If they don't clear, and I'd ask a tech about it, it is a much more serious maintenance item you don't want to skimp on!

pyrodex

Careful, now. You are in VIOLATION of the participant's agreement. I'd hate to see you get suspended!

And........
As a general rule, Chevys are NOT as reliable as Toyotas. Simply a fact!!!

neussl

There are interference engines and non-interfering (free-wheeling) engine designs. A free-wheeling engine is one that if the timing belt or chain breaks or jumps a cog, it causes no internal engine damage. Most Toyota engines are none interference designs (not the 1.5 Tercel or 2.4 Diesels, however). Most, but not all, other engines are interference designs, which means the valves will contact the pistons and destroy the engine if timing belt failure occurs. To find out what you have under your hood, go to www.gates.com

bud_light_dude

Looking at the Gates belt replacement guide, I only see belts on the smaller engined cars and compact trucks. I may be incorrect, but that incinuates to me that the belts are not used on heavier built trucks.

The only domestic trucks or cars I saw on the application guide were compacts, mostly 4 bangers.

Didn't see any Full size trucks on the application guide.

rs_petty

The most recent date I saw was '98. Two years old. The TLC 4.7 was listed, but not with a recommended interval change. By the time mine gets to 90k I'm sure they'll have the listing.

arkie6

Many if not most of your high end luxury and performance automobiles today use timing belts. Why? Because it is the best available way to turn multiple camshafts fast and efficiently. With everything there are tradeoffs, and the timing belts do require more periodic maintenance (i.e. replacement with a typically inexpensive belt).

There appears to be a lack of knowledge concerning how engines are constructed (you can't drive an overhead cam engine's cams with a gear due to the large distance between the crankshaft and the cams). And bud light dude is way off concerning belt stretch with todays timing belts. In fact, for a belt and chain of the same length (your typical timing chains are rarely as long as long as your typical timing belt due to engine configuration) I would bet that you would get more stretch (or elongation due to pin and link wear) with a chain than a belt.

The reason the Toyota 4.7 V8 uses a belt is because it is a dual overhead cam engine (thats 4 camshafts on a V8, similar in design to the Lexus LS/GS 400 engine), unlike Chevy, Dodge, and older Ford V8s which mount a single cam low in the block close to the crankshaft and uses pushrods to lift the valves. I'm not sure if the new GM engines use gears or chains to drive the camshaft, but the old GM engines use chains. I think that the new Ford engines are single overhead cam. Not sure if new Fords use belts or chains.

Another reason for using a belt verses a chain is that the belt has much less mass. This translates into less energy required to accelerate it and it also allows higher engine RPMs.

The reason small cars and trucks are listed in Gates belt guide and full size domestic trucks are not is because the smaller vehicles typically use higher revving overhead cam engines that use timing belts whereas the full size trucks (with the exception of the new Fords and Tundras) use single cam pushrod engines that don't use timing belts.

Hope this clears things up a little.

Alan

bud_light_dude

Well, your information is factual. I am not sure why you submitted it. I already knew all about that. I do feel you are incorrect about the belts and stretching. The whole reason full size trucks have not used a belt is for that very reason, not because of stroke length and such. Belts are very prone to slipping also, which causes timing problems that are very hard to diagnose properly unless by a very skilled tech.

The main reason belts are ever used is to limit destruction if they go out, slip, etc. to the rest of the engine components as well as they are simply cheaper in cost.

As far as using a belt vise chains or gears because they are superior in any way is simply a very false statement. Ask any highly skilled tech, and you will get the very same thing.

quadrunner500

But fortunately, the proof is in the pudding. Because if putting all those extra camshafts and tiny valves on top of the engine really did make it more efficient, it would be getting better fuel economy than the simpler pushrod engine with fewer parts.

But since it gets worse mileage, in a lighter truck, the obvious answer why Toyota uses them is because they don't have a truck engine.

tp4unc

Quad would put his 2 cents in. He does it to help ease his buyer's remorse(without much luck I might add). You bought too soon, Quad.

quadrunner500

Now don't get me wrong, cause I think you're alright. But that defroster won't keep you warm in the middle of a night.

Oh...so you drive a Toyota? (That don't impress me much) - Shania Twain

tp4unc

See topic 1421...post #34.

and,

"Don't be stupid."
-Shania Twain
LOL!!


You must really like that chick! I kinda prefer
Faith Hill myself. I wouldn't kick either one of them out of the bed for eating crackers, though! Oh well, it's nice to dream. Later.

neussl

Yesterday I was in the local Toyota/Ford Dealership where I used to be employed and they had a late model Explorer's SOHC 4.0 V-6 engine in pieces. Seems that the owner, stopped at a red light, had SEF (Sudden Engine Failure). The 4.0 Single Overhead Cam V-6 has two (2)timing chains, one running off the crankshaft on the front of the engine and the other chain running off the REAR of the engine (flywheel end). I have never seen an engine with this design before. Seems like the rear chain's plastic guide failed, let the chain jump and destroyed the entire engine. This engine is definitely an "INTERFERENCE ENGINE" as all 12 valves contacted all 6 pistons. End of story. This is a "customer pay" $4K to $5K engine replacement job. Fortunately, the owner is an attorney and I personally drive a Tundra 4WD V-8 for more than obvious reasons.

quadrunner500

We both know:

I don't have to worry about rusting floor pans.....

You don't have to worry about chicks eating crackers in your bed.

pcheng

I don't know if you've seen a modern timing belt lately, but they have teeth on them. They are also wider than a chain, and have deeper notches in the gear than a chain. And yes they are lighter than a chain. Looking at the two, they both have about the same chance of slipping (not very much).

As far as the number of valves versus gas mileage. The two don't have anything to do with each other. You use 4 small valves instead of 2 big valves to decrease the time of the air/exhaust needs to enter/exit the combustion chamber. Even though both 2 valve or 4 valve head can have the same valve area, the 4 valve setup will have a larger valve edge area. This allows the the mixture to get into/out of the combustion chamber faster. Also, 4 valves are used to increase the valve opening area.

Increased flow does not have anything to do with combustion effiency. It will allow higher top rpm and higher horsepower, which translate (loosely) to decrease gas milage.

If you want an example of this, compare an old 1000cc 2 valve motorcycle motor to a modern 4 valve motor. The new motor makes much more hp's, but the gas milage is terrible.

tp4unc

LOL! You're right about the chicks...the wife scares them away. She probably intimidates the rust, too!

meredith

After 30 or more days of inactivity....

this topic is being "frozen". It will be archived or deleted in the next 10 days or so.

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