It's been a while since I posted on E53 forum. I sold my 01 X5 4.4i in 2013, and bought 09 X5 3.0i. My E70 N52 is not powerful enough to tow my 3200lbs boat, which, with a tandem trailer and other things weighs about 5,500lbs.

I am thinking of giving my E70 to my teenage daughter and getting myself something that can handle my rig. I don't want to get a truck as I know I am not going to enjoy driving it.

To cut story short, I am considering buying 00-03 4.4i or 4.6is. For the most part it will be used used as my daily, and occasionally used to tow my boat. I am looking at one 03 4.4i with a tow package, and another 03 4.6is without a tow package. I need an advice on which vehicle I should get, and do have couple of questions:

* Does 4.6is M62 suffer from the timing guide problems just like 4.4i? Will replacing tensioners buy me some time before I have to face rather big timing chain expense?
* How difficult would it be to install an OEM hitch and harness on 4.6is? Is the OEM hitch for 4.6is same as 4.4i? Do I have to cut the bumper (I hope not) ?
* Would it be safer to get 4.6is without tow package and have assurance that it wasn't used for towing heavy things or go with 4.4i with a tow package and save about $2.5k ($1.5k price diff, plus $1k for hitch and installation)? The owner of 4.4i did say that he tow his boat couple of times.

It's worth mentioning that most of the towing will be done over the mountain passes, albeit for the most part short distances of 5 miles each way.