My question is what happens when you replace the head to the lower end. I've seen the low end go out from this. Is it because the compression comes up and the lower end can't handle it? 99 2.5l 246k .

 

Not really sure about the issue that led to the head replacement but I do know that if a headgasket goes and you get coolant in the oil it will often cause bearing issues. Not really sure about any consequences of increased compression being the issue. I would imagine that if the top end is getting bad to the point of needing the heads rebuilt or replaced then the bottom probably is pretty worn too. Probably better to just do a total rebuild.

 

???

A little more info

The lower end, crank, rods and pistons are made for stock compression ratio, for a 2.5l thats 9.1:1 ratio

So if you are using a stock head then there is no issue, if you are shaving the head to get higher ratio it still shouldn't be an issue, people do add turbos to these(2.3l/2.5l Lima) engines and if they run under 5psi boost the lower end will usually last just fine

If there is a problem in the lower end after a new head swap then the problem was there before, new head didn't cause it, just running the engine for xxxK amount of miles caused it

 

Ya. I figured as much. I have to do some tests before I get to that point. Compression test. I was just wondering about the lower end if I had to. If that's the case. Then I'll just put another engine in it. Truck is in good condition other than that. Just had the transmission done so what's another engine. Still better than a new car note 👍 thanks for the reply.