|05-31-2010, 10:03 PM||eBay Motors #1 (permalink)|
Join Date: Aug 2009
Location: las vegas
07.5 LMM towing issues
I just returned from a camping trip with my family. We were towing a 26ft toy hauler with 3 quads and the related gear, no water. I'm towing with an 07.5 2500 Duramax LMM 4 dr swb 4x4 with 305 55 20 Coopers zeon xts. I kept the speed around 60-65 mph indicated and calculated the fuel mileage at approx. 7-8 mpgs. Does that sound right to anyone? I expected better out of the truck since I sold my 05 GMC Yukon XL 4x4 with 8.1 liter and 4.10 gears and that was getting 6-8 while towing.
I also noticed the temp gauge would rise to about 220 or so before the fan would kick on and then it would drop back down to 210. Is this normal? I was towing through some mountainous terrain in central to southern Nevada, outside air temp was approx. 80 degrees and was I was not running the truck hard. Trans temp was right around 190-195 the whole time. The trans tunnel in the cab did get relatively hot to the touch also, is that normal?
The truck has 44K miles; a Banks cat back exhaust, cold air intake, deep sump trans pan, Cognito arms and accessories, Bilstein 5100 shocks, airbags, tonneau cover. Should I look into a tuner and a DPF delete pipe? I've also read that I maybe should have put on a larger pipe from the turbo out?
thanks for any help.
|05-31-2010, 10:09 PM||eBay Motors #2 (permalink)|
NewEST Spinny Thinggg
Join Date: Apr 2009
i would go with a dpf delete if your looking to gain mileage
06' CHEVY 2500HD CCSB PULLER/DD
Danville Billet S475
SoCal Stg.2 Heads
Mahle Forged Pistons .040 ovr
Floor it pump
|06-01-2010, 01:05 AM||eBay Motors #3 (permalink)|
Join Date: Nov 2008
Location: Orlando, Fl (Winter Springs)
rusw1, take it to dealer and check for updates for your truck. How much lift do you have? The higher, the less fuel mileage. Your tire size will affect mileage if you can't get moter to 'sweet spot' while towing. About 1600 rpm's. While towing, you should be in the 12-14 range unless your trailer is VERY tall.
2005 3500 LLY CCLB SRW, Allison, 3.73 posi, 285-17 Michelin on H2 wheels, Cognito tie-rods, 5400 xenon lts, 3500 fogs, Air-dog 150, 4" MBRP exhaust turbo back(kitty no-more), BD exhaust manifold, MBRP turbo down-pipe, MBRO IC tubes Mag-Tech deep sump tranny & rear dif, Banks Filter air-box, IOH kit(Mouthpiece) EGR bolck-off ,Amsoil remote oil filter & by-pass filter, Synthetic lube in engine, tranny, transfer, rear end . Thanks Alligator! :rockin
|06-01-2010, 06:05 AM||eBay Motors #4 (permalink)|
Join Date: Sep 2008
Location: Beer Tent Capital of the World
Did you have it locked out of 6th gear?
I get the best towing MPG's between 1800-2000rpm's
2003 Chevy 2500hd crew cab 4x4, D/A
Just a few aftermarket goodies
|06-01-2010, 06:12 AM||eBay Motors #5 (permalink)|
Join Date: Mar 2008
Location: Dubois, PA
the overheating is from the DPF...at least mine was. took it off and have never heard that fan kick on again.
Vehicle 2008 Black Chevy Crew Cab Short Bed Z71
Tires & Wheels 285/75/R16 Load Range E BFG A/T's on Stock Rims
Suspension Cognito UCA kit with Bilsteins all around from Nick at Nor-Cal Truck
Drivetrain LMM Duramax, Allsion 1000 Transmssion
Performance Mods EFI Live and DSP 5 By MMLMM, RBP downpipe back exhaust (no CAT or DPF), TransGo Jr, Mag Hytec transmssion and rear end covers, PPE Air Box Mod, Resonator Blocked, Auto Meter GS Boost, EGT, and Transmission gauges, Auto Meter triple pillar with speaker cutout. all from Tyler at Meyer Performance & Fabrication, LLC
Other Mods B&W Turn Over Ball, Air Lift Bags, Titan 52gal fuel tank, Wether Tech FloorLiners, SpeedLiner spray in bedliner, debadged whole truck except bow ties and D-Max/Allsion logo
|06-01-2010, 07:04 AM||eBay Motors #6 (permalink)|
Sounds like you're a great candidate for a DPF delete. Shouldn't see any issues with getting hot once you get rid of the DPF. The taller tires will hurt your mileage a little bit, but you shouldn't be seeing that bad of mileage
What brand of intake do you have? Some of them are actually worse than the stock intake and will pull in hot air from the engine compartment rather than cool outside air, like they're supposed to. This can increase engine temps and fan activity.
Let me know if I can help you out with the DPF delete. I run a DPF free LMM personally every day, so I can answer any questions you might have.
|06-01-2010, 05:39 PM||eBay Motors #7 (permalink)|
Join Date: Mar 2010
i pull a 35 foot 5th whhel that is 12-4 tall --- keeping @ 55 i get 12 and that running under 1500 rpm with the tow/haul set--- as soon as i go fast - the fule gauge runs down as fast as the truck --- pulling 70 or i get 8 mpg
I run 280/17 tire and have the full Banks set up!
|06-02-2010, 09:53 PM||eBay Motors #9 (permalink)|
Join Date: Aug 2009
Location: las vegas
I am interested in a DPF delete pipe. I'm already running the Banks CAI and Banks Monster exhaust. What type of tuner do I need? Should I replace my downpipe from my turbo? Will I still be able to pass annual emissions check or will I have to come up with a work around?
thanks for your help
|06-02-2010, 09:56 PM||eBay Motors #10 (permalink)|
Join Date: Jan 2009
Location: Green Acres OK By GOD
2008 CC SB 4X4 LTZ
6" ProComp lift
20" ProComp wheels
35" Xtreame A/T's
4" Iron Cross step bars
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