Regardless of the 12 valve or the 24 valve, the one ting you probably want to keep your eye on is the block number. The 53 block on the 24 valve has caused some people some problems. I'd watch out for that more than anything else.

 

That's good info. Where do find the block number? Is this only for 24 valve or is it also a problem for 12 valve?

 

Drew had some pretty good pics, but I didn't save them. I'm pretty sure they were at the bottom of the block towards the front.

 

I swear I just posed some info on this in this thread. . .where did my post go[&:]


anyway, the 53 block cast in brazil has a slight casting defect on the exhaust side of the block that can cause a crack in the water jacket. if you crawl under the truck and look at the front of the engine just above the oil pan you will see in pretty big numbers '53'. if you see something else you have a mexican cast block that for some reason tips the scales as the heaviest casting for any ISB block.

this only applies to trucks produced from 99-01

 

REALLY ??

I thought it was all 24 valve engines

 

I'm pretty sure if he's going with a newer truck he has to get the 24v seeing as how the 12v wasn't made after'98.

 

I never heard about the 53 until a few days ago. Guess its time to check the block and be wary.

 

Hey Silverline, do you have a 4.5" down pipe too or just 4" down pipe to 4.5" tube? The shop I got my exhaust at told me that they couldn't fit a 4.5" down pipe on my truck.

 

To tell you the truth I really don't know. It had the exhaust when I bought it and I never really looked at the down tube. I'm about to crawl under it tonite and patch a hole in the exhaust so I'll look at it. My guess is that your exhaust shop isn't wrong and that the exhaust is around 4" at the manifold and then expands to the full 4.5" after. In short its huge and its LOUD.

 

you got my interest so I went out and looked. Looks like its still the stock down tube with a 4.5" adapter on it and then the 4.5" on back. Guess I get to put the down tube on mylist of things to change out.