I recently returned from a trip towing my 8000 pound 5th wheel w/ my stock '03 HO Dually w/ 6spd manual transmission.
My real question follows the narrative just below.
One day I was climbing 6% slopes at 10,000ft elevation (80degF) in 4th gear no sweat and 1/4th throttle, and the next day (on a steep portion of UT 12 between Bryce Canyon and Capitol Reef NP) the ONLY gear I could hold was 1st gear almost floored at 2900rpm at 6500ft elevation and 100deg F. The signs indicated the grades were 8% and maybe a tad more.
There had been PLENTY of times on the trip I'd been well over 100degF (as high as 116deg F) at over 6000ft on steep grades and NO problem.
As soon as I changed my undies (the consequences of NOT topping that grade on a narrow 2-lane road w/ a 1000ft rise on one side, and a 1000ft drop on the other were not pleasant since there was no place to pull over, or back down the mile long hill), I pulled over and looked for loose turbo hose clamps or a burst hose/intercooler. Everything looked FINE.
We continued the trip, and for the most part everything felt fine, especially as we reached lower and less steep.
Now at home, we hooked a SnapOn scanner up and couldn't find anything obvious. The Control pressure in 5/6th at lower rpm (1600-2000) at WOT is only 18.5kpsi (it hits 21.5kpsi WOT in the lower gears at 2200-3000rpm). I have no gauges YET (which is part of my question farther down), so I can't say what the parameters were on that grade, but the truck felt like I'd swapped the Cummins for a Corolla engine, and I didn't like it one bit. It was making NONE of the torque I am used to feeling at 2000rpm, hence having to wind it out to 2900rpm to get up the hill in 1st at about 12mph or so (it wouldn't even hold 2nd at 2900rpm) . The engine was butter smooth always, idles like a Honda Civic and has always had plenty of grunt for me. Just on this ONE hill ONCE it let me down badly, and I need to find out why, then fix it.
As a matter-of-course returning home I replaced my AirDog lift-pump fuel filters, the TPS (since everyone said that at 130k mi it was close to needing replacement anyway), and the FCA (since the 18.5kpsi WOT at 2000rpm seemed low). The engine runs and feels the same after the replacements, which is not bad, since it feels fine at sea level (no hills anywhere close to here where I live in Texas). Hell, it felt fine an hour after the incident (though we didn't have another hill that steep).
Note that under ALL conditions the actual rail pressure (on the scanner) perfectly matched the ECU's Command Pressure, so I doubt I have a CP3 problem if I understand the system right.
I am about to buy some monitoring equipment (so I won't be so ignorant of the parameters after the next such possible incident), and I have several choices:
1) Mechanical Boost and EGT (Westach at $300) in a pillar pod.
2) Edge electronic monitor that sees a bunch of parameters
3) Bully Dog 40400 Gauge/Monitor Package for $300 (see bullydog.com/product.php?ID=1"]http://www.bullydog.com/product.php?ID=1)
4) Bully Dog 40420 Gauge/Monitor/Tuner all-in-one for $500 (See bullydog.com/product.php?ID="]http://www.bullydog.com/product.php?ID)
My understanding is that Bully Dog is considered inferior to Smarty Jr for the Cummins, but I am not THAT interested trying to make BIG HP gains, though perhaps 30-50hp more might be good for towing, and for only $200 more than for gauges alone, you get a tuner/programmer w/ Bully Dog that says it has a 50hp Tow Package that won't melt pistons (vs $500 extra for a Smarty Jr over the gauge package).
As I said, MOSTLY I want to be able to monitor things (EGT, Boost, Command and Rail Pressure, TPS %), and extra power is a distant second since towing "only" 8000-10,000 pounds the stock 300hp/500ftlbs should be sufficient w/ the 6speed I would think.
Sorry for the long, possibly confusing, post, but...
Opinions or suggestions?
Thanks-
Bob
My real question follows the narrative just below.
One day I was climbing 6% slopes at 10,000ft elevation (80degF) in 4th gear no sweat and 1/4th throttle, and the next day (on a steep portion of UT 12 between Bryce Canyon and Capitol Reef NP) the ONLY gear I could hold was 1st gear almost floored at 2900rpm at 6500ft elevation and 100deg F. The signs indicated the grades were 8% and maybe a tad more.
There had been PLENTY of times on the trip I'd been well over 100degF (as high as 116deg F) at over 6000ft on steep grades and NO problem.
As soon as I changed my undies (the consequences of NOT topping that grade on a narrow 2-lane road w/ a 1000ft rise on one side, and a 1000ft drop on the other were not pleasant since there was no place to pull over, or back down the mile long hill), I pulled over and looked for loose turbo hose clamps or a burst hose/intercooler. Everything looked FINE.
We continued the trip, and for the most part everything felt fine, especially as we reached lower and less steep.
Now at home, we hooked a SnapOn scanner up and couldn't find anything obvious. The Control pressure in 5/6th at lower rpm (1600-2000) at WOT is only 18.5kpsi (it hits 21.5kpsi WOT in the lower gears at 2200-3000rpm). I have no gauges YET (which is part of my question farther down), so I can't say what the parameters were on that grade, but the truck felt like I'd swapped the Cummins for a Corolla engine, and I didn't like it one bit. It was making NONE of the torque I am used to feeling at 2000rpm, hence having to wind it out to 2900rpm to get up the hill in 1st at about 12mph or so (it wouldn't even hold 2nd at 2900rpm) . The engine was butter smooth always, idles like a Honda Civic and has always had plenty of grunt for me. Just on this ONE hill ONCE it let me down badly, and I need to find out why, then fix it.
As a matter-of-course returning home I replaced my AirDog lift-pump fuel filters, the TPS (since everyone said that at 130k mi it was close to needing replacement anyway), and the FCA (since the 18.5kpsi WOT at 2000rpm seemed low). The engine runs and feels the same after the replacements, which is not bad, since it feels fine at sea level (no hills anywhere close to here where I live in Texas). Hell, it felt fine an hour after the incident (though we didn't have another hill that steep).
Note that under ALL conditions the actual rail pressure (on the scanner) perfectly matched the ECU's Command Pressure, so I doubt I have a CP3 problem if I understand the system right.
I am about to buy some monitoring equipment (so I won't be so ignorant of the parameters after the next such possible incident), and I have several choices:
1) Mechanical Boost and EGT (Westach at $300) in a pillar pod.
2) Edge electronic monitor that sees a bunch of parameters
3) Bully Dog 40400 Gauge/Monitor Package for $300 (see bullydog.com/product.php?ID=1"]http://www.bullydog.com/product.php?ID=1)
4) Bully Dog 40420 Gauge/Monitor/Tuner all-in-one for $500 (See bullydog.com/product.php?ID="]http://www.bullydog.com/product.php?ID)
My understanding is that Bully Dog is considered inferior to Smarty Jr for the Cummins, but I am not THAT interested trying to make BIG HP gains, though perhaps 30-50hp more might be good for towing, and for only $200 more than for gauges alone, you get a tuner/programmer w/ Bully Dog that says it has a 50hp Tow Package that won't melt pistons (vs $500 extra for a Smarty Jr over the gauge package).
As I said, MOSTLY I want to be able to monitor things (EGT, Boost, Command and Rail Pressure, TPS %), and extra power is a distant second since towing "only" 8000-10,000 pounds the stock 300hp/500ftlbs should be sufficient w/ the 6speed I would think.
Sorry for the long, possibly confusing, post, but...
Opinions or suggestions?
Thanks-
Bob
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