Is it only when braking or does it happen also when you are driving and abruptly let off the go pedal?

 

Do a search for "drone" problem. That might be it. I think it happens around 1800 rpm, around 55 - 60 mph, about exit speed. There is a fix for it.

 

Mine does the exact same thing, sumtimes mine does it while turning, sounds like a power steering pump on mine, but it doesn't make sense while braking

 

I don 't think it's the "drone" problem.

I'll pay more attention, but I think it makes the sound with or w/o the brakes. I don ;t believe it's a malfunction of any kind, I'm more curious about what is causing it.

 

Heard that, i paid way to much money for stuff to be f*ckin up

 

I noticed the exact same sound on my truck today. It seemed to only happen when I let off the throttle from a cruising speed and immediately got on the brakes. When I let off the throttle and coasted before applying the brakes, it only did it once or twice. It sounded like the engine fan kicking on (or a steering pump under full load) for about 1 or 2 seconds then it stops. Could it possibly be the tranny making noises until the convertor unlocks? 650 miles on my new truck and now this crap... Censored

 

Yeah, it kinda does sound like a power steering pump under load. (I'm pretty sure it's not the P/S pump but it does make that kind of sound). The sound abruptly ends as if a valve or solenoid is shutting and I only notice it after driving at cruising speeds (freeway) and then abruptly letting off the throttle and braking (off ramp).

Again, I don't think it's a malfunctiuon (hoping), but I would like to know what it is! :think:

 

Is your truck an LLY?


The sound you are describing to me sounds like the VVT shutting down when you lift off the pedal?? My LLY does it but not my LB7.

 

Mine does the same exact thing. It is the torque coverter unlocking, and, according to my diesel technician is normal. I have driven several 05's that do the same exact thing.

 

Mine does the exact same thing, sumtimes mine does it while turning, sounds like a power steering pump on mine, but it doesn't make sense while braking

Actually, I believe the brake system hydraulic booster is powered (for lack of better term) by the power steering pump. If that is the case, then it can make sense. Hopefully some of the more knowledgeable folks will jump in and provide the details.

 

Mine did it and I took it to the dealer and they said there was a valve that needed to be upgraded they did it and now I have no noise at all.Give it a try,Mark

 

My '05 does not have the drone but it does do this usually after a highway run. I THINK it is a hydraboost/steering noise. I'll be calling my service writer on Monday about a possible valve replacement.

Thanks racecar.hotshoe!

 

My '05 does not have the drone but it does do this usually after a highway run. I THINK it is a hydraboost/steering noise. I'll be calling my service writer on Monday about a possible valve replacement.

Thanks racecar.hotshoe!

Thats when mine did it and when pulling my boat,It got real loud when I put on the breaks,I would have them replace the valve in the P/S...Mark

 

Please let me know what the service writer says. Mine does it too.

 

Hey, thanks for the replies. This is what makes this site so great - everybody getting involved and helping out!:ro)

Anybody that goes to the stealer please post here and let us know what they say. It sounds as if this noise is a common occurance, at least with the LLY's. If there is actually a problem I know we would all like to know!

 

i have the same noise but only when im towing

 

Well this is gonna sound really weird, but the other day when my truck was making the noise, my wife and I had decided to take a day trip up to Yosemite. Now that I'm back down in the valley, I haven't been able to make my truck duplicate the noise. I'm stumped, so I'll be watching this thread closely if anyone figures the problem out. Oh yeah, here's 2 cool pics from the trip:

 

I live about 10 miles up the road from Lilwes in the Central Valley of California. I have about 5,000 miles on my truck. I drove it up into the Sierra's to the 7,000 ft elevation level. I also heard the groaning sound from the power steering pump at the elevation. Never heard it before, and haven't heard it since. Could elevation be a key here?

 

The drone is a hydraullic boost to the brake system when there is a low presure condition, such as when you have been on the highway for an hour and not touched the brakes.

 

i have the same noise but only when im towing

Same here. Just like skeetdiesel said, it seems like it's only after I've been on the highway for a couple hours, and hit the brakes on an exit ramp.

Is there a TSB on this? I've got 11,000 miles on my rig.

 

The drone is a hydraullic boost to the brake system when there is a low presure condition, such as when you have been on the highway for an hour and not touched the brakes.

Well, this would not explain my situation. My truck was doing it on winding mountain roads. No way I could go for an hour without using the brakes...

 

I would have guessed torque converter. Mine does it in towhaul, right as it's making the shift down to first at a stoplight. Without towhaul it does it much sooner in a higher gear.

 

mine has done this for over a year it seems like something is binding at about 1300rpm or rubbing they changed my steering pump and no help my powersteering sucks nuts also

 

Word I got.....

Well talked on the phone to my service "consultant" at James Wood in Denton where I bought the truck almost a month ago. Explained to him it sounds like the hydraboost is vibrating/buzzing at low rpm's, most obvious when slowing down from a highway run. He talked like it was not a common occurence and to make sure I could duplicate the noice so a tech could hear it. It's such a pita to go to the dealership I think I'll wait till it gets worse before I take it in.

This issue and the start/stop clunk because of dry driveshaft/yoke splines are the only complaints I got. To tell you the truth I expected much worse.

I can freeze my passenger out until they beg for mercy even at 98 degree temps, jerk my boat around like its some kind of kids toy, and get 16-17mpg in bumper to bump traffic. What else could I ask for, I love this thing!

 

Hey guys, take a look at the THREAD that I started today about what appears to be the same problem that you are talking about!!! I didn't find this thread until after I started my own. Sounds like we are talking about the same problem though. What valve in the power steering unit did they actually change so that I can mention it to my service guys? How many of you had this valve changed out and did it cure the problem? This noise sure is annoying and doesn't seem to be a "normal operating noise". Any input will be gretly appreciated!

 

Wasted Income- what is a "TSB"?

 

Tech Service Bulletin.