I have an old 1995 2500 with 120,000 miles, so far the engine has performed flawlessly with
nothing done to it...except PM..

A friend of mine keeps agravating me about the turbo...he says things like "wait till the turbo fails and see how much that costs etc...

Anyway I have a few questions:

What is the prupose of the wastegate control, how does it work/actuate...??

How is the turbo lubricated?

How long does the turbo usually last on these engines?

What can I do to prolong Turbo life???

How do I tell if it is starting to go bad??

When I shut this engine down I can here a smooth/quiet spinning sound I assume this is the
turbo turning down after the engine is shut off.

This is just my work truck and has been carefully maintained and easily used...

Thanks!!!!!

 

the biggest thing is to let it cool down a bit before you shut it off. i like mine to get to 300 degrees on the egt gauge before i shut it down. and my stock turbo lasted 259k till it started to have the bearings wear enough to start touching the sides. and the last 60k miles have been over 400rwhp. turbos are not that bad to buy, but i would not even worry about it.

 

Nuff said.


Mine has 234,000 and no problems thats smaking 40+ boost normally for the last 30,000 .

 

The wastegate limits maximum boost. The wategate controller (the "can") is connected to boost, when boost reaches the maximum amount for that controller the controller opens a valve in the turbine housing. This valve allows exhaust to bypass (waste) around the turbine and directly into the exhaust pipe.

The turbo is lubricated by engine oil, tapped directly off the top of the oil filter head on a Cummins. The oil drains back into the block through a pipe on the bottom of the turbo. The turbo gets oil pressure as quickly as the main bearings on start-up.

The turbo often outlasts the rest of the engine. There is really only one moving part.

Proper cool down, avoiding excessive boost levels, and not barking the turbo are good ways to make it live a long life. Keep it under 35 psi if you want it to last. Don't jump out of the gas at high boost levels to avoid barking, roll off the pedal gently if possible. Barking is when the pressurized air from the intake flows back out through the turbo, it causes rapid speed changes in the turbo which are rough on the shaft and bearings. It really does go "woof woof woof" when you bark it, so you will know if it happens.

Nasty scraping/shrieking noises or lots of blue smoke out the tailpipe are bad signs. If you pull the intake hose off when doing oil changes, grab the nut on the end of the turbo shaft and try to wiggle the shaft side to side and in and out. Any in and out is bad. If you can't make the wheel hit the housing on the side to side play, things are alright.

The noise you mention is exactly what you think it is. The turbo spins at several thousand RPM at idle and it takes a few seconds for it to stop.