Screaming truck

[Rawze]

Just adding this here for reference. Maybe will help others who are having similar issues but did not find any metal shavings or damage upon inspection.

(01-16-2018 )Rawze Wrote:  ...
The most common loud noise from a turbocharger is more like a screech. Sort of similar to someone letting the air out of a metal baloon. That is the most common sound they make. Everyone swears it is a sounds like the turbine is scraping against the walls of the turbine housing at high speed, but in fact, that is almost never the case at all. The most typical culprit is a manifold gasket or the turbo mounting gasket itself. If in fact the turbine was scraping against anything, the housing would be full of metal shavings and the damage could very easily be seen by simply looking at the turbine(s) with the intake/exhaust piping pulled back.

- The other sound they make is a similar screeching sound and that can come from the VG ring being slap worn out on an old turbo. Never heard if from a factory reman.


I.E.> It could very well be a mounting gasket issue if it is the classic "schreeching" sound you are hearing if it has recently been changed. Someone could have under-torqued the bolts the book calls for 45-ft lbs on the mounting bolts, but in all actuality, it should be 75 ft-lbs.

here is a reference to this: http://rawze.com/forums/showthread.php?t...1#pid30841

A lot of shops these days are too damn lazy to even bother to torque one in the first place, so i would re-torque the mounting bolts to 75 ft-lbs as a start. Next, it could be a warped exhaust manifold with a gasket leak either at the turbo mounting flange, OR at one of the exhaust ports.


Where did you get the replacement turbo's?

Some detailed history?

Who did the de-mandate and who did all the mechanical work for the de-mandate?. PM me if you don't want to say it publicly.

How high can your boost and pyro gauges get up to under a hard pull up a big hill?

Part of this original post: http://rawze.com/forums/showthread.php?t...7#pid22387