98 fl70 w/ 8.3 issues

[MMeier]

Buddys honey wagon in Colorado has a low boost issue as of late. Will only get to 11 lbs of boost under load then falloff to 6 or 7. Also has a sound out of exhaust that sounds like an exhaust brake being on all the time, rig has no brake or any crap on it that can cause that.... did something crawl up in muffler and make a home , turbo gone south ( intake side appears fine he said )? Apparently getting fuel, belches black when under load, any ideas welcome !!

 

[BDaugherty]

Check air filter/intake for restrictions, check turbo intake and exhaust wheels, check for exhaust leaks, check for boost leaks. Also check fuel supply and afc diaphragm. Make the checks in the order listed.

 

[Wayne M.]

It's possible for a baffle in the muffler to collapse. If the basic checks above don't show anything, I would get the muffler off and try it.

 

[mwilson]

Are you sure it doesn't have a PAC Brake on it? Some of those did. If it were stuck closed it would behave in a similar manner.

 

[MMeier]

It's possible for a baffle in the muffler to collapse. If the basic checks above don't show anything, I would get the muffler off and try it.

What he is looking at doing first.

 

[MMeier]

Are you sure it doesn't have a PAC Brake on it? Some of those did. If it were stuck closed it would behave in a similar manner.

No brake on it yet, he does want to get one on the truck since alot of the places it goes to involves big *** hills, and the drivers nerves are wearing thin on some runs ! Says it sounds like his 6.0's on warm up !

 

[mwilson]

See if you can score the.last 6 of the vin. We see the occasional Catalytic Converter on older stuff. Worth a look.

 

[Wayne M.]

See if you can score the.last 6 of the vin. We see the occasional Catalytic Converter on older stuff. Worth a look.

Prolly as you were typing this, I was just bragging about you to my own parts boss. Lol.

 

[MMeier]

It's possible for a baffle in the muffler to collapse. If the basic checks above don't show anything, I would get the muffler off and try it.

Ding ding, we have a winnah !!! Muffy came apart internally, tried straight pipe, too damn loud, could be heard 2 countys over !!!

 

[Wayne M.]

Nice. Now help him pick out a short case so it'll sound like a cummins should!