While towing a 27' travel trailer up and down some steep, twisty roads, it seemed that the turbo started making more noise under load than normal. It also happens now when not towing, just driving. When the throttle is pushed harder, it seems like air is being dumped out of the turbo. Standard gauges all read OK, looking at the turbo doesn't show any missing bolts, clamps, gaskets(they are OEM but don't look blown.). How do I check the turbo for issues? The truck seems to drive normal, just is noiser. Any thoughts will be appriciated.
Oh yeah, the engine has 412k kilometers. Runs like a clock.
Thanks,
Cam

 

possible air leak on the intake lines. how's the boost?

 

Mine was an intercooler boot, whistled like hell!

 

Ok, thanks for the suggestions, I'll check 'em out. Don't have a boost gauge but the engine seems to respond like it always has, maybe just a bit less 'omphf' but that's probably me panicking.

 

Wastegate stuck?

 

So I hauled another RV today. Without a trailer, the truck scoots along like normal but the noise when the turbo is working just seems to be louder than before. That is the same when towing the trailer. When up to speed and cruising, the noise is normal. It also seems that it may be a little down in power when pulling up a hill. Although I was a little lighter on the throttle because in the back of my mind was 'holes in the intake lines causing higher EGT's'. So I wasn't working the engine as hard.

When I returned home, I thoroughly checked the intake rubbers and there isn't any holes or leaks. I don't know how to test the wastegate operation but after reading some descriptions of wastegate operation, I'm wondering how I can check to see if it is stuck a little open. BUT, from the articles I read, I should be way down on power and that's not happening. I think I will get someone I really trust to do a brake stand while I'm underneath watching for lever\spring operation. Dangerous but I need to have the turbo spool up under load to see where this noise is coming from. I must be nuts. Safety first.

 

You can make a leak checker out of a PVC pipe cap, a compressed air fitting, and a rubber coupler (I think the brand name is Fernco) from Lowes or Home Depot. You take off the intake hose to the turbo and put on the leak checker. Pressurize it to normal operating pressure, around 20 PSI, with the engine off. You should be able to hear any big leak, soapy water will find the little ones. This method should be a bit safer than doing a brake stand

Hope this helps

 

I have seen several trucks where the lower boots rub against the inner fender metal, and develop little tears in the sides of the boots.
Boost pressure is lost and turbo noise increases.
Laying under a truck doing a brake stand doesn't sound like the next move to me...yikes!

 

If you find out what is making the extra turbo noise,let the rest of us know so we can make the same adjustment and enjoy the music.