Hey Guys,

I have been noticing a groaning type noise from the engine bay for awhile and it slowly seems to be getting worse. I used to only notice it after hard pulling in the heat of the summer when pulling off the highway, but now it seems to always be there. It makes the noise between about 1,500 and 2,000 RPMs, and sounds possibly like a bearing going bad on one of the pulleys.

On a 200 mile drive home yesterday, I paid more attention to it, and the noise is consistently there; meaning I can hear it cruising at a constant speed, accelerating, slowing down, and even revving the truck in neutral at a stop. If I really get on it, the noise from the turbo spooling and injectors firing quickly drowns it out, so it's not that bad yet.

I pulled it into the garage once I got home and had a friend rev the engine to 1,500 RPMs while I checked all the pulleys by putting a large dowel on each of them and listening for any odd sounds. We even checked the turbo, and it sounded fine. The sound seems to be coming from somewhere in the valley, so my best at this point is possibly the fuel pump?

The A/C and alternator are both relatively new, the tensioner pulley felt good when I replaced the serpentine belt a few months ago, and the power steering pump is really quiet. The only other possibilities I can think of is possibly the fan clutch bearing or vacuum pump pulley.

Any ideas?

I'm getting ready to take the truck on a 2,500 mile trip (no towing) on Wednesday, and I would have liked to get it into the shop to get whatever is wrong fixed, but I don't think they would be able to pinpoint it either at this point. I'm not too concerned about it breaking down and maybe it'll be loud enough by the time I get back that I can better track it down if none of you have any ideas.

Thanks in advance!

 

Can you hear the noise when you're standing in front of the truck at idle? at 1500 RMP with no load do you hear it? Based on your description, I would think either clutch or (and this is my best guess) that the down pipe is contacting the firewall when the engine rocks under load. I would bet that the DP is the culprit. They have been known to loosen up and drift a little over time and get into the firewall making the sound you described.

 

Thanks for the suggestions DIY!

I can't hear the noise standing in front of the truck at idle, but I can hear it at 1500 RPM when in front of it. I've had many clutch issues in the past with this truck, and this new sound is not one I've heard before, although I think I'll try holding it at 1,500 RPM with the clutch in and out to see if the noise changes.

I do like your suggestion about the down pipe. I'll definitely take a look at it when I get home to make sure it hasn't loosened up and is now resting against the firewall. That would be an easy (and free!) fix if that is the source of the noise!

Thanks again!

 

I am doubting that it is a clutch issue since you have already replaced the DMF with a SMF Valair unit, but it could be a bearing or something in the tranny growling. I still think the DP is the most likely culprit.

 

DP or vacuum pump pulley is my guess.

 

The truck self-diagnosed itself yesterday and decided to spit the idler pulley next to the tensioner out onto the pavement when I pulled away from a stop light in Salinas, CA. I heard a banging noise and then something hitting the pavement, and I said to my passengers, "Huh, that's not good!"

Fortunately a gas station was on the other side of the intersection, so I pulled in and in doing so quickly realized it was a pulley issue of some sort due to no power steering (I can't believe what beasts these trucks are to try and turn with no power assist!). I ran back to the intersection to recover the pulley and decide my plan of attack.

Fortunately I remembered seeing a Ford dealer about 4 miles back, so I called them to see if they had the part and could replace it that afternoon. The new pulley was $50, and they could install it as soon as I got there.

Not wanting to wait for a tow, I nursed the truck back to the dealer with no power steering, brakes, cooling, or charging and drove it right into the service department. I got a couple odd looks from customers as I was pulling in with my flashers on and jumping out with the old belt in hand.

$135 installed and an hour later, I was back on the road to Santa Barbara. I was quite impressed I got away from a dealer repair that cheap and quickly, so I will give Salinas Ford's service department "two thumbs up!"

I'm just glad the pulley decided to give out there instead of up on the Siskiyous the night before in the middle of a raging rain storm. Not only would I have had to wait for a tow late at night, but braking that truck with no power assist coming down that grade would have probably been something I remembered for a LONG time!

After thinking about it, I am pretty sure I overlooked that pulley when inspecting the noise last weekend. Seems odd I didn't notice it when I checked out the tensioner pulley, but oh well, at least it wasn't something worse!

Here's to hoping that's the first and last of automotive surprises this trip!

 

Wow! Glad it ended as well for you as it did. That could have been bad.
I guess Glenn gets a silver star for being the closest to getting it right.
At any rate, here's to hoping that's the last of your problems for this trip!

 

ya Nate, I never get the gold!

SHOpar, My wife will never ride with me going north down the Siskiyous again. Beautiful day and when we got to the top it was fog so thick you could cut it with a knife. I was going about 45 mph and she was screaming at me to slow down. I had two things going thru my mind, burn up the brakes trying to slow down just to get rear ended by a truck or trying to maintain what I had and hope I could keep seeing the road. When the time came to go back south she checked planes, trains and ships until a guy in the camp ground told us its stair steped going south and is no problem. It wasn't, LOL.