newbie for this forum and to dodge

[tdrat]

tdrat here, I posted about my 2007 6.7 on 7/27/10. I asked several questions and MORBIUS answered those qustions for me. I have been thinking about his advice to run the automatic in 5th gear, especially when towing my 5th wheel on long distance runs, so it will get the RPM's up to where the engine runs more efficiently and the DPF would be less likely to soot-up. Qustion... Will the torque converter lock up if I run in 5th gear with tow/haul engaged? If so, is the trans cooler sufficient to cool the transmission?
Thanks for your help.

[morbius]

Hello Tdrat,

Glad I could have been of help. In tow/haul mode with the tranny limited to highest gear of 5th, the torque converter will behave as normal (or it should). What the tow/haul mode does is tell the computer to be more aggressive in how it up/down shifts helping the engine to maintain the proper rpms.

Can the cooler handle it, it will. The factory cooler is the not the biggest or the best, but can handle it since it based on averages. You are not going to be pulling that trailer up hill in both directions for the whole trip. I know of a person that hauls large RV trailers professionally with his truck and always runs in 5th with tow/haul mode and his truck (a 2008) is over 300,000 miles with no issues.

I would suggest in investing into an Edge Insight gauge. It plugs into the ODBII port. Set it up to monitor DPF status and tranny temp. It will be the best thing you can do. That coupled with your existing gauges and you learn how to best handle the truck with trailer and prevent your DPF from having issues. This what I have in my truck and worth every penny spent.

Hope that helps.

Cheers.

[Dixiedawg]

Ditto the recommendation about acquiring an Edge Insight. I would recommend installing the EGT probe also. Had no idea when it was in the regen mode until the Insight was installed. Now I monitor EGT, tranny temp, boost, and ECT. We tow a fiver (gross combined weight 20K) and are currently 4000 miles into an 7000 mile journey and are keeping records of regen cycles and mpg. We have an auto with 3.73 gears, and are completely stock. We left from the Pacific Coast in early July and just left NJ yesterday working our way back west. It has been hot so the A/C has been used extensively, and we have averaged 11.59 MPG by manually keeping records. The EVIC in not accurate, which is no surprise. When we finish the trip I will post all the stats, including regen cycles. So far regen cycles have varied between 40 miles and 235 miles driven based on various driving conditions.

[79ta]

I have a 2009 2500 4x4 6speed auto with just 2k miles and recently deleted the dpf, unplugged the egr and loaded the smarty jr programmer. What a difference, I have a 4" mbrp mufflerless exhaust and the truck sounds great, not too loud and with the improved throttle response and 3 to 4 mpg increase, it was well worth it. The best thing is I can return the truck to stock in about 2 hours without a trace. I pull an open car trailer a few times a year and with the programmer on tow mode the truck didn't know the loaded trailer was behind it. These trucks are awesome.

[tdrat]

tdrat here... I asked a question in my first post about RPM range when towing my 5th wheel and "Moribus" answered and suggested locking into 5th gear when towing, but keep an eye on tranny temp. My question is: Does the torque converter lock up when manually shifted to the lower gear?

My understanding of torque converters are that they generate more heat in the unlocked position because they are driving through a fliud hook-up only which has a slight amount of slippage and thus will generate more heat, especially when under load.
tdrat

[tdrat]

Hello Morbius,
I didn't see your 2nd message until after I made my comments about torque converter operation. If the trans works "as normal", but only in a more agressive way, then the torque converter should lock-up in tow/haul and when locked in 5th gear. Also, I apologize for misspelling your screen name in my second message. Thanks to all... for the help and advice.
tdrat