Strange noise when towing

[JordanB]

I was towing my friend's 35ft. 5th wheel this weekend and heard a strange noise about 1 1/2 hrs in to the trip. Under steady throttle, no noise, but when passing or going up a hill there would be a loud "eeeeeee" noise. It is definitely not turbo whine if that's what you're thinking. As soon as I'd let off the throttle a little bit it would go away. My guages all registered normal - 190 transmission, 200 engine, etc. The truck wasn't defueling or anything - had plenty of power. No weird smells. Nothing out of the ordinary except for the noise. After dropping off the trailer I never heard it again. I think I've heard this noise once before when I was getting on it with the family on board, but I could never duplicate it. I've hauled some large loads before in the bed but this was my first time towing with the truck and I was a bit concerned. Does anyone know what this sound is or do I need to just take it in to the dealer. I'm not sure I can duplicate this without a load.



(fyi, the egt's were constant at 900 most of the trip, only getting up to 1200 or slightly higher when going up long hills)

 

[Bob Wagner]

sounds like it could be the fan clutch

 

[JordanB]

Would the fan clutch make that kind of sound or do you mean a slipping belt?

 

[rbattelle]

Could also be rear end noise (depending on your definition of "loud noise").

Ryan

 

[TAbbott]

Could be just the fan noise. It moves a lot of air and has very little clearance in its new engine mounted shroud. Rapidly moving air through tight spaces can make some weird noises.

 

[JordanB]

It's not the rearend. It's coming from the front. I don't think it's just air. I would think it would be doing it more often, not just the couple times over the past 19,000 miles.

 

[Slow Six]

Maybe a leaking hose or clamp on the intake from the turbo to the intercooler or from intercooler to intake. These can make all sorts of weird noise from a shreik to a sort of farting sound and may only happen when you are in it (making higher boost) Just a thought as I've had it happen.

 

[JordanB]

I'll definitely check out the intercooler clamps! Your the 3rd or 4th person who has suggested this and it makes a lot of sense! I'll let you know.

 

[BVANR]

I had a strange squeel under acceleration when I had a load too. It was only loaded only under full pull. Never figured it out until it became worse and started vibrating lightly... then a lot. $45 u Joint later... all better. Not sure if it was the change of angle with heavy load or the weight itself, but the early stage of going out was just noise... sounded like steel fingernails on a chalkboard..... just a thought for something easy to check.

 

[JordanB]

A u-joint seems odd but I'll check everything this weekend. Thanks for all the suggestions.

 

[BVANR]

I agree, but it's hard to determine the sound you here from here

 

[JChott]

Not sure how much weight you had on the rear but if I put 3000 lbs or so in mine, the driveshaft pushes too far into the back of the transmission and squeals a bit when on the throttle hard - axle rotates a bit and pushes the driveshaft even farther into the transmission. Didn't know what it was until I climbed under there with a load on and noticed the rear seal was damaged. Dealer replaced the seal but said there was nothing wrong with the truck. Maybe see if your rear trans seal is okay, mine was not leaking, just torn rubber on the outermost part.

 

[JordanB]

Yeah, I never got around to checking anything last weekend and I've been dead tired from work. Therefore, I'll will check things out this weekend. :-laf I was able to duplicate the noise yesterday by showering down on it while the A/C was on and no extra weight. My A/C was on when I was towing, too. Hmmmm?

 

[DrDiesel]

First check that issue with the A/C on/off. Verify if it only occurs with the A/C on. Then you can isolate it further from there. I would also check my turbo shaft for play. If you bearing is failing, under a heavy load the impeller can grind into the housing and make a strange noise. It would most likely be the exhaust impeller that makes contact with the housing.

 

[wcjp]

I know my fan clutch is loud when it kicks in. Usually only in the mountains under a load.

 

[JordanB]

Okay so I finally got around to tightening my boost tubes this weekend. So far so good! I've yet to duplicate the noise. I was able to tighten down 14 of 16 bolts. The two clamps that hold the boost tube going into the intercooler were impossible to get to without removing the rubber deflector thingy. I don't have any of the stupid plastic clips to put it back on when the clips break. I don't know how tight you should tighten the other 14 so I just winged it. Oh well, it's not squealing yet so I'm happy. Then again I may have tightened them down too tight and could crack the damn tubes! :-laf Thanks for all the input fellas! I'll keep you updated. I do have another question but I'll pose it in another thread. It has to do with a part-throttle surge when holding it in 2nd gear.

 

[Rdunkin]

Your truck "should" have a METAL intercooler. If it has PLASTIC tanks on the ends the noise you hear is probably the Pass. side tank leaking. Mine sounded like a vacum cleaner for 10 minutes at a time until it failed.

 

[JordanB]

It's metal and the sound has returned.

 

[houseoffire8]

Noise under load

I have been getting a squeeling noise when under load. I think its the tension pulley! Went to the shop and told them, they said it is the turbo then changed thier mind and agreed probably tension pulley. They are getting the part and will call when they get it. 2007 heavy duty 4dr dually 5. 9L only 49k anybody else have this problem?

 

[guldam]

My 12valve makes a whiring/rubbing/grinding sound when pulling my boat up tight steep hills. It only does it when it has shifted from 2nd to 3rd, with overdrive off.



I thought transmission was going out. My mechanic buddy was with me this weekend and the truck made that sound here and there, and he said, no way the transmission. He thinks fan clutch.



I'm just going to drive it till it quits. The ghosts in this truck will drive you nuts if you let them.



Then there's the vibrating sound coming from the 4wd shifter. Hold the knob in the center and the noise goes away.



GulDam