I recently had to do a bunch of work to my truck since a couple years ago when I first bought it, and now I'm a at a point where I could use some advice/opinions. But I guess I'll start with some background info. I got an 07 2500 5.9 Cummins.

Last Sunday, I was at a drive through and shut off my engine to place my order. Upon starting the truck, I had a very loud rattling/clanking noise and immediately shut the engine off. Got out of the truck and realized there was coolant pouring everywhere, WTF?! Crawl underneath the truck (massive line of cars behind me), and find the belt snapped and wrapped around the crank pulley. Used a razor blade and a screw driver to get the belt off so I could get the hell out of there and wait for help. I figured belt must have snapped and went into the radiator, called a buddy to get the belt.. well, I was WRONG!!! PO bought a POS $35 aftermarket tensioner that snapped right in half at the bracket, launched into the radiator and snapped the belt. $600 later, I got it all fixed and I was lucky I know a guy who towed my truck home for a case of beer. Now I've got a few questions/concerns, and I'd appreciate the input.

1- I've noticed (since my fan is still off) with the engine running there is a bit of wobble in the crank pulley and the power steering pulley. I'm more concerned about the crank obviously, but is this "normal" or anything to be concerned with? I was wondering if the belt binded it up or something.. truck is running perfectly normal though. I've noticed a light "squeaking pulley" noise - might have been there with the fan on and I never could hear it.

2- I've read many forums about electric fans on these Cummins and how they are no where near as effective as the mechanical fan. I personally have no gripes with the mechanical fan, other than removing it might improve the warm-up time in winter months. I already have/use a winter front but it still takes forever for the truck to warm up. This last week it's been 70-80s and no overheating without a fan on and lightly towing a few times. Should I keep the electric fan and also put a piece of cardboard in front of the rad in the winter, or consider electric? I don't tow heavy often, but I want my truck to stay as capable as possible. This lead to me question the electrical fans with or without a shroud. The top of the line fan systems out there (flex a lite) draw 5500 cfms and there are reports that isn't enough for heavy towing. I was wondering if maybe the whole radiator shrouds on those fans are the issue, as the fans can't draw enough cfms and the remainder of the radiator is blocked off by a shroud. Just a though, sorry for the super long post. Thanks.

 

I would try to stick with the stock fan setup. It was desgined that way for a reason. Personally, I would go with an OEM fan replacement if possible.

 

I'm not too familiar with the cummins, but the gas 1500 use a harmonic balancer on the crank pulley
As far as I know a slight wobble is normal there
It will wobble as it dampens engine vibration
Im not familiar with the 5.9 diesel setup

Keep the stock fan setup

 

Thanks for the input guys!

 

I'd lookup the symptoms of a bad harmonic balancer
You can also find info on how to inspect it. Look for any cracked, deteriorating or swollen rubber. Check for any play by hand. Check for oil leak where the crank pulley meets the engine

Just to be safe

 

So far no leaks, no play in the crank pulley. I've got the fan back in so it's gonna make it more difficult to check up on it.