13speed Posted June 7, 2017 Report Share Posted June 7, 2017 I am ready to order my VNR tomorrow but have one final decision to make and Volvo is making it a bit harder. The lowest gear I can choose with a 455-Eco and non OD trans is 2.50. (Non Eco was 2.67) 295/75/22.5/40.6 dia = 1345@65 mph. 11 R 22.5/41.8 dia = 1307@65 mph. 65 is my intended cruise speed but I might hit 70 to pass or if I am bob tail. I wanted 295's just to keep the hitch a 1/2 inch lower but it probably wont matter that much either way. I am not sure how much of a difference 38 rpm is going to make. The only other thing I did consider is that by the time the tires are 1/2 or more worn the rpm's will be a lot closer to 1400 with the low pro's. Thoughts? Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
Pete Kildow Posted June 7, 2017 Report Share Posted June 7, 2017 Wish the rest of the engine makers. Had the same setup as Cummins. You can use there Power Spec. And it allows you to out the use, Engine, Trans, Tires, weight. Then it will tell you what speed at RPM's. Along with what the truck is going o run up what % of grade. Pete Link to comment Share on other sites More sharing options...
Alie&Jim's Carrilite Posted June 7, 2017 Report Share Posted June 7, 2017 In all honesty, 38 RPM isn't going to make a difference during the time you own the truck. If you were planning on being a hay hauler, running 1million+ miles in the next 6 years, then sure a little fuel here and there makes a difference. But for your intended purpose, I don't think it would matter. At 65mph, I would pick the gear that puts you as close to the middle of the torque curve as you can. Alie & Jim + 8 paws 2017 DRV Memphis BART- 1998 Volvo 610 Lil'ole 6cyl Cummins Link to comment Share on other sites More sharing options...
13speed Posted June 7, 2017 Author Report Share Posted June 7, 2017 11 minutes ago, Alie&Jim's Carrilite said: In all honesty, 38 RPM isn't going to make a difference during the time you own the truck. If you were planning on being a hay hauler, running 1million+ miles in the next 6 years, then sure a little fuel here and there makes a difference. But for your intended purpose, I don't think it would matter. At 65mph, I would pick the gear that puts you as close to the middle of the torque curve as you can. Well, Volvo says cruise rpm's should be 1200-1500 so 1350 splits even which is the low pro's with new tires. I will creep up from there as the tires wear. The 11-R's would hit that after some wear. I am a bit nervous after having my Ram lugging with 35" tires and factory 3.42's and then re-gearing to 4.10's and having it be pretty rev'd up at 65. My milage went down big time. I do not want that to happen when I have to feed a extra 6.1 liters. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
GeorgiaHybrid Posted June 7, 2017 Report Share Posted June 7, 2017 I don't think you have anything to worry about if you are concerned with lugging the engine. At 1350 rpm or so, you will be in the middle of your power band. You have a little more giddy up and go with this engine compared to a Fiat. 2017 Kenworth T6802015 DRV 38RSSA Elite Suites2016 Smart Prime Link to comment Share on other sites More sharing options...
NoDirectionHome Posted June 7, 2017 Report Share Posted June 7, 2017 Are those your numbers or Volvo's? The tire diameters seem inaccurate for "real" tires. You need the revs/mile from the tire manufacturer. Are you ordering a direct drive (1:1) or overdrive (.78:1) transmission? Overall, for a modern truck with an "RV" load, I'd personally consider 1350 RPM too high for cruise. "There are No Experts, Do the Math!" 2014 Freightliner Cascadia DD16 600hp 1850ft-lb 18spd 3.31 260"wb SpaceCraft S-470 SKP #131740 Link to comment Share on other sites More sharing options...
GlennWest Posted June 7, 2017 Report Share Posted June 7, 2017 My truck is older but for comparison, if I get just in or slightly low of peak power rpm minimum, I get best mpg. Of course this is flat country side. The truck barely notices my Teton. Could Volvo be figuring in heavy towing normal for commercial towing? 2003 Teton Grand Freedom towed with 2006 Freightliner Century 120 across the beautiful USA welding pipe.https://photos.app.goo.gl/O32ZjgzSzgK7LAyt1 Link to comment Share on other sites More sharing options...
13speed Posted June 7, 2017 Author Report Share Posted June 7, 2017 3 hours ago, NoDirectionHome said: Are those your numbers or Volvo's? The tire diameters seem inaccurate for "real" tires. You need the revs/mile from the tire manufacturer. Are you ordering a direct drive (1:1) or overdrive (.78:1) transmission? Overall, for a modern truck with an "RV" load, I'd personally consider 1350 RPM too high for cruise. The diameters are straight off of Bridgestone's web site for the tires I am getting. The trans is a NON overdrive 1:1 final drive. 295/75=497 11 R=512 2.50 is the lowest choice Volvo is giving me. 3 hours ago, GlennWest said: My truck is older but for comparison, if I get just in or slightly low of peak power rpm minimum, I get best mpg. Of course this is flat country side. The truck barely notices my Teton. Could Volvo be figuring in heavy towing normal for commercial towing? I am sure that they are basing things on 80K not 45-47K which I will be. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
13speed Posted June 7, 2017 Author Report Share Posted June 7, 2017 9 hours ago, GeorgiaHybrid said: I don't think you have anything to worry about if you are concerned with lugging the engine. At 1350 rpm or so, you will be in the middle of your power band. You have a little more giddy up and go with this engine compared to a Fiat. I am not worried about lugging or a lack of power. I would not want to be much under 1300 though. I don't want to be over reved and wasting fuel either. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
GeorgiaHybrid Posted June 7, 2017 Report Share Posted June 7, 2017 The sweet spot on my Cummins is supposed to be 1400 rpm. I have mine geared to run 55, 65 and 75 in the top three gears at that rpm. It will run at 1220 rpm in 13th at about 63 mph but it will drop down a gear for a hill of any size. Either way, I don't worry about it that much at the 12,000 to 15,000 miles per year max that most of us might put on our trucks. 2017 Kenworth T6802015 DRV 38RSSA Elite Suites2016 Smart Prime Link to comment Share on other sites More sharing options...
13speed Posted June 7, 2017 Author Report Share Posted June 7, 2017 Well then what is the consensus, Low pro or high pro??? Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
GeorgiaHybrid Posted June 7, 2017 Report Share Posted June 7, 2017 I went with the Bridgestone Ecopia low rolling resistance tires in a steer tire in the front and lugged in the rear (single axle and wanted the extra traction over an all position). Mine happen to be 295/75 tires and are what Scrap recommended. So far I am happy with them. They are the Ecopia R283 steer tire in front (40.3 dia and 516 rpm) and the Ecopia M760 in the rear (40.7 dia and 511 rpm). 2017 Kenworth T6802015 DRV 38RSSA Elite Suites2016 Smart Prime Link to comment Share on other sites More sharing options...
Alie&Jim's Carrilite Posted June 7, 2017 Report Share Posted June 7, 2017 31 minutes ago, 13speed said: Well then what is the consensus, Low pro or high pro??? My quarter said heads on the flip.... Go Low... my .02... Alie & Jim + 8 paws 2017 DRV Memphis BART- 1998 Volvo 610 Lil'ole 6cyl Cummins Link to comment Share on other sites More sharing options...
13speed Posted June 7, 2017 Author Report Share Posted June 7, 2017 1 hour ago, GeorgiaHybrid said: I went with the Bridgestone Ecopia low rolling resistance tires in a steer tire in the front and lugged in the rear (single axle and wanted the extra traction over an all position). Mine happen to be 295/75 tires and are what Scrap recommended. So far I am happy with them. They are the Ecopia R283 steer tire in front (40.3 dia and 516 rpm) and the Ecopia M760 in the rear (40.7 dia and 511 rpm). The Ecopia are the no up charge option from Volvo. The 283 in front and 710 out back. Glad to hear you are happy with them. As you had said earlier we won't be putting on much over 10K per year so I suppose it won't be a huge difference. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
GlennWest Posted June 7, 2017 Report Share Posted June 7, 2017 True but if I were ordering a new truck, I would want it geared just for my coach, not 80k. Also that is plan on keeping it and not resale to commercial later. 2003 Teton Grand Freedom towed with 2006 Freightliner Century 120 across the beautiful USA welding pipe.https://photos.app.goo.gl/O32ZjgzSzgK7LAyt1 Link to comment Share on other sites More sharing options...
beyerjf Posted June 9, 2017 Report Share Posted June 9, 2017 I would go for the lo-pro because they are by far the most common of the 2 sizes on the market, will be cheaper and easier to replace. Jeff Beyer temporarily retired from Trailer Transit 2000 Freightliner Argosy Cabover 2008 Work and Play 34FK Homebase NW Indiana, no longer full time Link to comment Share on other sites More sharing options...
13speed Posted June 9, 2017 Author Report Share Posted June 9, 2017 On 6/7/2017 at 10:52 AM, GlennWest said: True but if I were ordering a new truck, I would want it geared just for my coach, not 80k. Also that is plan on keeping it and not resale to commercial later. Yes. 1 hour ago, beyerjf said: I would go for the lo-pro because they are by far the most common of the 2 sizes on the market, will be cheaper and easier to replace. See that is weird. Gregg had said that about the 11R's Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
beyerjf Posted June 9, 2017 Report Share Posted June 9, 2017 Easy to check, just ask the Volvo dealer you are ordering the truck from. It may vary regionally some, but in the US at least I am pretty sure Lo-Pro 22.5's are hands down the most common truck tire on the market. Jeff Beyer temporarily retired from Trailer Transit 2000 Freightliner Argosy Cabover 2008 Work and Play 34FK Homebase NW Indiana, no longer full time Link to comment Share on other sites More sharing options...
13speed Posted June 9, 2017 Author Report Share Posted June 9, 2017 If I could get a lower gear in the back it would be low all the way but with the choice I have it is pushing me to 11R's Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
CampClownPete Posted June 14, 2017 Report Share Posted June 14, 2017 This is so easy it's not even a choice! Option 1: If your engine is lugging down in Top Gear what do you do? Downshift! Option 2: If you're over-Revving in top gear what do you do? Slow Down! Some states, such as AZ, you will get run over if you're not towing at least 70 mph in a 75 mph state! In other words, gear your truck for 75 mph Bobtail! Your transmission has options for slower cruising speeds but once you're in Top Gear your tranny has run out of options and so have you! Link to comment Share on other sites More sharing options...
13speed Posted June 14, 2017 Author Report Share Posted June 14, 2017 6 hours ago, CampClownPete said: This is so easy it's not even a choice! Option 1: If your engine is lugging down in Top Gear what do you do? Downshift! Option 2: If you're over-Revving in top gear what do you do? Slow Down! Some states, such as AZ, you will get run over if you're not towing at least 70 mph in a 75 mph state! In other words, gear your truck for 75 mph Bobtail! Your transmission has options for slower cruising speeds but once you're in Top Gear your tranny has run out of options and so have you! Well, That would be nice except that Volvo has limited my choices and the lowest gear I can get is a 2.50 so the only way for me to gear for higher speeds is to choose 11R's. With the 11R's I will be pretty good for 60-70 in 12th so that is what I am going to go with. I really don't want to tow over 65 to maybe 70. I remember going 75-80 back in CO with a W900 day cab and a end dump trailer and that just felt crazy fast so I do not think I want to tow my house at those speeds as well as pay for the fuel it would consume. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
dgrulke Posted June 15, 2017 Report Share Posted June 15, 2017 Just my 2 cents.... have you thought about going with the ATO2612 overdrive tranny. You could then get a 2.67 rear end and be running our engine at a lower rpm even with the lo pro tires. Link to comment Share on other sites More sharing options...
13speed Posted June 15, 2017 Author Report Share Posted June 15, 2017 17 minutes ago, dgrulke said: Just my 2 cents.... have you thought about going with the ATO2612 overdrive tranny. You could then get a 2.67 rear end and be running our engine at a lower rpm even with the lo pro tires. I was originally told by Gregg that going with the non OD was the shiz because of less parasitic losses so I went with it. But now I am second guessing after reading up on it a bit. I can see if I can change it since the order was just placed. I really did not want the 11R's. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
Pete Kildow Posted June 16, 2017 Report Share Posted June 16, 2017 On 6/14/2017 at 7:37 PM, 13speed said: I was originally told by Gregg that going with the non OD was the shiz because of less parasitic losses so I went with it. But now I am second guessing after reading up on it a bit. I can see if I can change it since the order was just placed. I really did not want the 11R's. That's why I want a 13 speed. Run in Direct and keep the speed at 62 to 65 MPH. But if I need to run faster there's more above that gear. And in 13th, it will let me run 7 0 to 75 MPH and still be good to go. Pete Link to comment Share on other sites More sharing options...
13speed Posted June 16, 2017 Author Report Share Posted June 16, 2017 10 hours ago, Pete Kildow said: That's why I want a 13 speed. Run in Direct and keep the speed at 62 to 65 MPH. But if I need to run faster there's more above that gear. And in 13th, it will let me run 7 0 to 75 MPH and still be good to go. Pete I love 13 speeds (there might be a hint about that here somewhere) they are really fun to drive and there is always the right gear but...The ishift is just so damn good. Even after 20 years of truck driving I am still not as smooth as it is. The ishift also makes it possible for my wife to drive when needed and me if I was ever to get hurt so it is the only option. Chris, Tracey, Aria & Lola 2018 Volvo VNR 400, D13 I-Shift 2018 NH 48' Majestic Link to comment Share on other sites More sharing options...
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