Was hauling some horses earlier and was thinking about what the tyical RPM range to run at when pulling a grade. I have this 94, 4:10's, around 10k i was pulling, 7% grade, I was at about 2500rpm or so, maybe a little higher doing 55+, that about right, or is that turning the motor to fast? I know fuel consumption sucks at that but I was pulling against an 04 cummins of my buddies and wanted to see how it did.
The biggest consideration is if you are lugging the engine. Good test is if you can accelerate (not a fast increase in power but the ability to increase your speed at all) in the gear you are in. If not you probably need to drop a gear.
Another good telltale is exhaust temperature if you have the gauge. If the temperature is rising it would probably be a benefit to downshift one gear as well. With the modifications you have listed it would bed a good idea to keep track of exhaust temps to keep from overheating things if you pull on a regular basis.
Dave / Believer45
__________________ THANK YOU to all the heroes in our military and all the heroes at home who wait for their safe return. I am humbled by and grateful for your service and sacrifice.
'95 F250 ext cab long bed, PSD, 5 speed, 2 wheel drive, 3.55 gears, 286,000 miles, Edge Evolution CTS (LINK TO MY REVIEW), LUK clutch, homemade REAR BUMPER, open element AIR FILTER, 36" ARE contractor cap. With tools, full of fuel and me on board (300 lbs) steer 3620, drive 3860 total 7480.
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The biggest consideration is if you are lugging the engine. Good test is if you can accelerate (not a fast increase in power but the ability to increase your speed at all) in the gear you are in. If not you probably need to drop a gear.
Another good telltale is exhaust temperature if you have the gauge. If the temperature is rising it would probably be a benefit to downshift one gear as well. With the modifications you have listed it would bed a good idea to keep track of exhaust temps to keep from overheating things if you pull on a regular basis.
Dave / Believer45
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Thanks Believer, yeah I was able to increase in speed if I wanted to, but I didnt want to burn THAT much fuel, as for the guages I am going to order pyro/boost/water temp in about a week or so, thanks.
When pulling hard, I don't let mine drop below 1900 and when I downshift it'll bring her back up around 22-2300 or so.
I notice your tranny & gears are the same as mine, not sure about tire size, I have 215/85R16's. At 22-2300 in 5th, I think I'm around 60 mph. About 2700 gets me up around 75, that's about as high as I take it. I really don't like running it that high, I try to keep it down below 2400, but on the long runs I usually end up in the 2700 rpm range.
I'm getting about 8.5 mpg with a GCW of probably around 20-22,000
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1995 F-350 XLT Crew Cab Dually 5 spd - Basically Stock - Used everyday for work & play (pulling 1989 36' Airstream Landyacht 5th wheel around the countryside to stock car races). I've owned the truck since new. I'm fortunate enough to be the 4th owner of the Airstream.
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... around 10k i was pulling, 7% grade, I was at about 2500rpm or so, maybe a little higher doing 55+, that about right, or is that turning the motor to fast?
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That's about right.
Diesel engines are designed to run right up against the red line all day long. Of course, they will gulp down the fuel when they run wide open, so I like to back off a few hundred RPM. Usually when mountain climbing, I put it in direct drive and cruise at about 2,400 to 2,500 RPM to the top of the pass.
But yeah, you need a pyrometer to be sure you aren't working the engine too hard. On mine, I usually climb mountains at 1,100º to 1,200º exhaust gas temp (EGT), which usually works out to about 55 to 60 MPH on 7 percent grades when grossing 17,500 pounds, or a bit less EGT when grossing 16,000 pounds.
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My Sierra Blanca in the sig pic was a great pickup for 11.5 years. I sold it last year. Replacement is a 2012 F-150 EcoBoost SuperCrew Lariat.
Fellas, after reading this thread, I called Dale at Tymar, and his thought were so. He said that the Marine Strokers are designed to run at 2655 all the time, so that in his opinion was the max that they should be run all day long. Running higher than that for short periods should be fine, but that diesels are not designed to be high rpm engines. Just thought I would share Dales advice on this thread. Do not know if that helps or not, just what he said and probobly what I will follow for my personnel towing limits.
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1997 ECLB F-250 4X4, TAT e4Od,4.10 Open Diffs,Superwinch Manual Hubs, 265/75/16 Force 4 AT's, DP Tuner F-5 5-Position (Stock,Hi-Idle, 40 Tow, 40 High Alt Tow, 80 Econo ),3"DP,4" Exhaust,Tymar Intake,Full gauges. Intercooled. ATS Turbo.
Pulling heavy, 23500 in the mountains I will go into the hills at 2800 rpms or so and down shift around 2200 to keep the torque and horepower higher. Works good for me. 130000 miles and still on the original stock trans and engine uses no oil between changes.
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Y2K 350 DRW PSD Lariat CC LWB 4.10 auto trans, TLS, Mag-Hytex Diff cover,Amsoil in Trans and Diff, Pillar mounted Spa tech dual gauges, aux trans cooler.Fumoto oil drain valve. Oil Guard bypass filter. AIS, 3 1/2 down 4 inch ex
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