Transmission pump sound?????

[AWebber]

Saturday 21st... ... . I spent a bunch of time under the truck today, new info posted after the replies that are already up. It doesn't sound like the transmission.

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My truck has recently started making a lower pitched whine than what comes from the turbo. The sound can be heard in park if you have someone rev the engine up while I listen from under the truck (not very loud when in park and sitting inside truck), it seems to be coming from the automatic transmission. Definitely not coming from around the turbo area.



When driving it is much easier to hear than in park. The sound can be made to rise and fall with the throttle, can even make it sound like a siren!! It is most noticable at lower speeds, above 35 it is hard to tell if it is still there because of the road noise. It rises and falls with the rpms of the engine and can be heard under much lighter acceleration than what is needed before the higher pitched turbo is heard. The noise is noticable on the flat, doesn't need to be going up hill.



It has been around 30 at night and 45 in the daytime. The weather has been this temp off and on for a couple months but the noise only started recently. My drive to work is mostly downhill and takes about 25 mins, I can still hear the whine but it is much quieter than when I start the drive. The uphill trip going home warms everything up good and the noise is gone. The oil level in the transmission is where it should be.



I was told it sounds like the transmission pump and is nothing to worry about unless it gets much worse and doesn't go away when hot. Does that sound correct (sounds like a good diagnosis to me)? Any ideas on what it might be if not the transmission pump? Any others have the same sound?

Thank you for any info/advice.

 

[MColp]

I also have the lower-pitched whine and it seems more pronounced when the engine is

cold. It sounds just like a siren. It started after I had the truck about 3 days. I am coming up on 7500 miles on my 05 and the sound hasn't gotten any worse. I drives me crazy but I have no desire to take it to the dealer unless it gets worse.

 

[nick05]

i would have to say that the trans fluid is just not wramed up to temp yet. the trans sounds like or is working a little harder until the fluid gets flowing.

just keep a good listen out for it and make sure it don't get worse. otherwise dealer time.



nick

 

[Diesel Power]

hate to say it but i think is not fluid related. it sounds like a fluid pump or servo in your valve body, take it to your dealer to get it checked out. good luck :-laf you should have the pressure checked on the transmission, that usually will find the problem.

 

[AWebber]

Thanks for the help guys

Thank you for posting info for me.



I drove about 120 miles today and the sound never went away when everything was warmed up. The day that I made my first post I checked for noise carefully all around the front of the truck. Then I laid on a piece of cardboard under the drivers side while someone held the engine at different rpms. I didn't have enough cardboard to reach to the passenger side and I couldn't get under that side because there was a curb along that side. If only I had time (short lunch break at work) to check it the other side the info I posted would have been different.



After getting back from the trip today I thought I would check all the clamps for the intercooler, turbo + intake. Seeing as though I had to remove the airbox to access some of the clamps I decided to take the intake boot off the turbo and give it a spin. It spins freely and has a very small amount of side to side play (normal?). None of the clamps seemed loose but most of them got snugged down a little more.



I started the truck hoping but not expecting the noise to be gone..... it was still there. Time to clear enough snow to get under the truck with my creeper. I had my son hold the throttle at different rpm's while I went creeping around under the truck. The sound was louder on the passenger side and seems to be in the exhaust. The exhaust is stock with catalytic converter still in place until reaching the muffler. I've had a 20" Magnaflow (welded in place, not clamped, with the 3 stock hangers for mounting) on for about a month now. I does sound louder than when it was first installed, maybe the packing has "settled in". The sound seems to be loudest in the section after the cat and before the muffler. I need to go do some searching to see if the cat or muffler breaking down can be the cause of this noise. It probably is the turbo I can hear but it isn't the high pitched turbo whine that I'm talking about. The normal high pitch sound is still there when it should be.



Sorry to have lead people down the wrong path when I first posted, I should have spent more time crawling around beneath the truck.



Thanks for reading folks, maybe someone other than myself learned something from reading this, other than thinking "darn diesel newbie"