JCT

thanks Vulcan,

I DO like my truck and hope that in no way did i seem like I was unhappy. and i know I need to watch the details in order to make better money.

thanks for the tip on shifting, after a year and 1/2 of the auto it might take me a few days to get that down. so i appreciate any info you pass on..


hope to see you out there.

 

Jarbo,

Give us some updates once you get under a load.

I am interested in JCT ...but they cannot take me till after Jan 8th

Thanks

 

From talking with the recruiters...i have the impression you must be almost perfect to

get hired on at JCT

They are very very selective

 

Shiftint at a low rpm might give u better mileage but I don't see the torque thing happening. I pull weight of 90k + and the engine bogs sometimes. Low rpms lug the engine. Lugging is bad on crankshaft and bearings causing premature decrease in oil pressure. I've seen bearings replaced at 200k miles. U could literally see the indentation in the bearings.

 

Don't forget you can turn on progressive shifting in the computer in most trucks, but then it acts like a governor when you hit the lower RPMs in the lower gears, so that might not work as well as doing it yourself.

 

good luck that's all i got to say.

 

Well I think you should do some research on these new engines 07 to present. They are designed to run at low rpms. Torque declines anything over 1300 rpm. Torque pulls the trk. Not horsepower. The more hp the more fuel you burn. I'm sure with you pulling 90+ you need higher rpm. We don't run that heavy so what vulcan suggested is perfect for our type of loads.

 

.When I went to school to be a mechanic back in 89 I could swear those big diesles were designed for torque.in fact. Torque has been the thing since almost the beginning.but the 5 year truck driver knows more then the 8 year driver. 15 year retired mechanic.1100 rpms is too low. 1200 minimum.pull any engine apart and u can tell which engines ran low rpm

 

Like I said its true that may happen on the pre egr engines. For example the acert cats are spec'd to operate at 1250-1300 cruise range. And you can lug them to 1000 rpm. So if you didn't know that then sure I believe I know more than you. Plus vulcan's experience plus kevin rutherford's experience.

 

think of it like this. lugging the engine might save on fuel becuase your not using as many fuel squirts due to lower rpm. BUT, what fuel squirts you ARE using is going to be a longer squirt because your throttle is opened more to make the engine work harder at the lower rpms. not only are you opening your throttle more, your allowing more air into the piston chamber. making more pressure, causing abornmal wear on the piston skirts. to the point you can get piston slap. your also causing a hammering of the pistons to vibrate down to the bearings. making the bearing slap against the crankshaft causing the bearing to wear out. thus, increasing the gap between bearing and crank. thus, lowering your oil pressure. ALSO, the pressure your putting on those pistons at the lower rpm with wider open throttle has also been known to break the piston rings. specially since probably most of you aren't using your fans to keep the engine precooled, instead you let them come on when that temp gets to 210. and shut off at 200. motor gets less wear and tear if you keep the engine running as cool as possible. we all know that metal expands with heat. and one last note. wider open throttle at lower rpms putting more fuel then necessary also means more emissions into the atmosphere.

don't matter what year or brand the engine is. you can't change the murphy law that happens from lugging the engine. 1200 rpm. anything less is lugging. bobtail can do it. but i wouldn't with full gross.

the whole reason the egr was implemented is becuase the govt wants to get rid of the external blowby engines have been putting out until 2004. they want that blow by to recirculate into the compression chambers and not vented out to the atmosphere. there's also a govt subsidy for older trucks to have catalytic converters installed. and mandatory for the fuel to not put out the black smoke by way of reduced amounts of some chemical i can't think of right off hand.

google engine blow by. somewhere there's a sight that talks about the egr law for diesel engines.

we have 5 trucks at work. 2 have egr and no blowby tubes. 05 and 06 model. the other 3 are 99, 96, 88. all have blowby tubes. and yes the 2 newer trucks get half the mileage of the older trucks.

you all might have trucking experience, but i didn't see any of the names you listed been driving longer. or having actual years of mechanic experience.

and i beleive this forum was for everyone to learn from one another. not bicker about who thinks they are smarter then whoever. wisdom of a person should be shared. not thrown back. i don't brag to know everything. i'm here to learn just like the rest of you.

now let's all get along.