Turbo Replacement

[gmenor]

What type of turbo replacement should I get for my 95 Burb? Is there any place I can get one for a reasonable price? Part number? Present one not sounding good.

[gmctd]

There are two on E-Bay now.

First, where guy sez he's helping to reduce someone's inventory, is a GM-4.

Second, where it's been in a guys garage for a while, is a GM-8. It is factory improved over earlier GM-4, replaces -4 and -5 models, is direct bolt-on.

[gmenor]

gmctd,
Thanks for the response. Is the GM8 a direct bolt on or is there any modification that needs to be made? I read somewhere that there is some modification's that has to be made on the 94-95 engines.

[Randee of the Redwoods]

I'm trying to swap on the GM8 now on my 94. I stripped one of the turbo nuts(by sheer stupidity) so it's been delayed, but, it is a true drop in swap. The only change is the routing of the wastegate hose. Rather than shoot under the a/c lines, it will now have to go over as the GM8 wastegate diaphram is mounted on top of the turbo. Aside from that, bolt on and go. As soon as I get some time to cut off the stripped nut(I had to guy an inverter to run my Dremel), I'll let you know how it turns out.

[Uncle Wally]

I spent some time searching the web for rebuilds when I did mine. 500 seamed like an average for the gm4. If I remember correctly it was a little more for the gm8.

I wanted more power, so I stepped up to a non-wastegated version from peninsular. For only 250 more, I figured I might as well do it now, and only pay once. Everything was a bolt on with exception to the oil drainback line. That required some work to get to bolt up and not leak. It will get changed in the next couple of weeks while I have the engine out for other issues. If you don't chip it, there will be a code for boost set. JK has a chip that can take care of that.

Waldo

[gmctd]

After the engine is at running temps, shut it off.

Remove the intake duct, and check the compressor blades for scratches, nicks, chunks missing, or bent blades.

Grasp the shaft with finger and thumb, check for side-to-side, and up and down play (radial). Should be minimal just after shutdown, with no blade-to-housing contact at any point.

Check the shaft for in-out play (axial). Should be less than any side-to-side movement.

Shaft should spin easily, should not immediately stop.

What are you hearing that indicates a problem?

[gmenor]

Thanks for all your response. gmctd what I am hearing is a loud metal to metal grinding sound from within the cab (right side behind the heating vent). Can't hear it clearly under the hood with all the other things turning. It has been blowing (white) smoke under a load and it does not pick up as it should. The beast just turned over 165k. I bought it used and the idiot I bought from had wired the waste gate shut (coat hanger) and cut about two inched of intake gasket from the rear of the intake manifold. Changed that out to solve the oil problem blowing all over the firewall along with the vacuum pump. Had it about three years now.

[gmctd]

Sounds bad - the "look and feel" test will tell that tale.
Observation is more than 50% of troubleshooting techniques.

White smoke is un-ignited fuel, where the fuel had never reached combustion temps.
Could be excessive fuel injected, or late injection from timing chain stretch

Black smoke is un-burned fuel, above combustion temps, where combustion had started, but lack of oxygen resulted in flame-out.

[ 12-12-2003, 03:28 AM: Message edited by: gmctd ]