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+--- Thread: Turbo and MPG... (/showthread.php?tid=2282)
Turbo and MPG... - dhirocz - 10-20-2017
Getting the hang of driving for mileage. I have to say, it's certainly different than 'set it and forget it' with the cruise, but so far I'm definitely seeing a difference.
Last week I installed a new paccar CAC. Saw another increase in mileage. I'm right at 13mpg driving @ around 3 psi of boost, 58-60 mph, empty tank trailer. Not a big mileage difference bobtail...not to bad considering I'm running on knobby tires.
Question is, while I'm loaded, my mileage is all over the place. I normally run 78-80k loaded, but it doesn't matter what I do...mountains, flat, slow, fast, not alot of difference like there is when I'm unloaded.
I'm still getting VGT out of calibration errors, so at 710k now, a step in the VG arm, and a stock turbo and actuator, I'm thinking the ECM is loosing it's ability to control the turbo...it's getting close to that time. Sometimes it pulls fine up a hill loaded at 12 psi, other times it wants 20+ on a similar hill. I don't think I'm seeing the problem unloaded because I'm hardly using the turbo. Thoughts?
RE: Turbo and MPG... - ynot - 10-20-2017
If it's the original turbo it's probably pooched an time for a new one.
Almost sounds like it's got too much play an it's sticking open, if ya got C-term try monitoring the the vgt commanded an actual position going down the road see of the are even, also if you step on it watch for wild swings in the actual position vs the commanded. That may give you a hint on what's going on in there.
_vgt_actuator_position
_vgt_actuator_position_commanded
;)
RE: Turbo and MPG... - dhirocz - 10-20-2017
I'll work on getting a copy of calterm. Been meaning to do that anyways.
I do notice I get the check engine light for this most often when I'm riding downhill loaded using the Jake's...
RE: Turbo and MPG... - ynot - 10-20-2017
Ya it's definitely sticking, the actuator is trying too close down for the jake but it's getting stopped along the way, mines been that way for a couple years now won't close past 55%, my solution I've got it set too not go past 50% an I don't use my jake lol.
But I don't do any out west mountains so it's not a big deal.
Ive seen some videos on YouTube of the pickup guys taking the exhaust housing off their mini VGTs an cleaning the sliding vanes cause I guess soot builds up behind them over time. Unless you ring has a grove wore in it then there's not much you can do.
RE: Turbo and MPG... - dhirocz - 10-20-2017
That's a shame. Seems to work fine otherwise, but if the nozzle is hanging up, that would explain it.
Time to cough up the money for a new turbo and actuator I guess. Funny, the CAC died before I could replace it...next on the list was the turbo and actuator. Here's hoping the head doesn't do that since it was next lol
Last time I checked, my local KW wanted $4000 for a reman turbo and a new actuator. Usually good on prices, but I'm not too impressed there. Ive got another he561ve here at the house, functional but basically a core. Best bet still OEM reman, or has the community here got any better options?
I've rebuilt turbos before, but all these kits floating about seem to be china shi#t. I don't do china shi#t lol...nor am I trying to gamble on something like a turbo.
RE: Turbo and MPG... - bazdan902 - 10-21-2017
There's a guy in Indiana that preacherboy knows that supposedly has some good reman turbos. I was told the guts of them are new holset not rebuilt. Pucketts's mechanical is name of the shop. Price was far cheaper then dealer, seem like good guys. Cummins doesn't necessarily have an outstanding reputation for their reman turbos nor warranty claims. I'd give Puckett's a try
RE: Turbo and MPG... - JMBT - 10-21-2017
I would DEFINITELY NOT put on a reman turbo from Cummins! That was a huge mistake I made a couple years back. It lasted a whole 35K miles. The nut on the compressor side wasn’t torqued properly during the reman job and it came loose and fell off into the compressor side blades, sounded like a rock in a squirrel cage. My wife was driving and got it shut down immeadiately, so no engine damage was done. It still cost me a $3500 tow bill to my brother’s house, and a bunch of missed work while I rounded up all the parts to do it right. Cummins did give me the $3650 I paid for the reman off of the brand new turbo I bought from them at $4450. But they fought it at first, even told me there were no new 451ve’s available. But we got through all that bullshit and had them source one straight off the line at the factory.
Buy a New one and save the headache...that’s what I learned!
RE: Turbo and MPG... - dhirocz - 10-21-2017
...so you were able to get a brand new one instead of a reman? I was told that was a nogo...though the new trucks obviously get them from somewhere. Who was able to get it for you?
Cummins makes a good engine but I try to stay away from anything recon. I'll always spend a few bucks more for new.
$3650 for just a reman? f$%k they are proud of these things aren't they? I wonder what holset would say if I called them about buying one...
RE: Turbo and MPG... - JMBT - 10-21-2017
DH: Yes, they told me the same thing, that no new ones were available. After calling all around the Midwest, we finally found a dealer, Cummins in Tulsa, OK, that came clean and said they could get a new one off the assembly line in Memphis, TN, but it was $4450, without the actuator, and unpainted. The new actuator was $1100. That was in 2015.
If you search around, you will find someone that can get you a new one.