Danny's X5 4.6 Thread

[X53Jay4.8is]

Originally Posted by dannyzabolotny

In theory it wouldn't be all that much more work to pull the heads off, since you need to remove all the timing components anyways. That being said, if I were removing the heads I would just do this whole rebuild as an engine-out job. Doing a head job with the engine still in the X5 would be miserable, there's hardly any room on the sides of the engine.

I personally didn't see a reason to do a valve job— the engine never really went out of time so the pistons and valves never met. Thankfully the dealer that was selling it at the time stopped driving it completely once the guides went.

Yeah, I don't foresee anything going wrong for the next 100k miles, aside from the usual stuff (alternator/water pump/pulleys/ignition coils). I don't think there are any issues with the rod bearings, given that it's still a pretty low-revving engine that uses regular oil, versus a high-revving exotic oil-using engine like an S54. I'll send off an oil sample for analysis when I do my next oil change, just to see how everything is.

There would really be no reason to pull the head on the 4.6is engine. The only thing that goes that needs attention on these is timing chain, guides, tensioners and vanos. These engines are pretty much bullet proof once the attention is is given to the aforementioned items.