Engine/Transmission (1998.5 - 2002) 280k, should we do injectors and VP44?

[steved]

21MPG?



Wow, If I was Guaranteed 21, I would De-Bomb Mine immediately, no questions asked We all know how much money we have Thrown @ trying to get the best and better mileage, I am happy to get 17. 4 all around Mixed driving, I think that is ok.

However, good luck with upgrades and please make sure you update us with #'s . . .



JoeLee

He's gotten 21mpg almost from day one... always had calculated.



I don't know whats so hard to believe... I got low to mid 20s with my 99 driving highway. 3. 55 rears go a long way to providing good mileage. I can average 21mpg with my 3rd gen and 4. 10 rears... a lot has to do with the way you drive.



And I'm not getting into this debatein this thread, as I'm trying to figure out what to do with his truck for PM, not mileage.

 

[blacksheepdiesel]

Steve,

The injectors will last for a long time without rebuilding. If you are unsure of their condition pull them and have them tested by a competent shop and that will tell you what direction to go. If you want better fuel mileage you could go with an injector that provides that.

If you are uncomfortable with the VP because of the miles on it go ahead and put a new one on.

Godspeed,
Trent

 

[FLynes]

Steved,



If it were me, and I was looking for peace of mind while towing, I would go ahead and replace that VP44. IMO, you're playing with fire, if you don't. I would also change the injectors to the RV275's; they do give you a better power curve and a nominal increase in MPGs, but any increase is better than none.



As for MPGs, 21MPG for a 3. 55 truck doesn't sound unreasonable. At 60MPH, my '01 3500 with 4. 10 gears got around 17MPG.

 

[darkhorse]

21 mpg is great. Quite believable to me as I get 19-20 in stop & go 2 lane gravel road driving. I get around 25 at a steady 65mph. All hand calculated but odometer error factor unknown.

 

[steved]

I probably aleady know the answer to this question, but if we upgraded to the 275s, would guages be required... remember, this is a 62YO retired person, not some *kid* like myself. That would be my reasoning to stay with a stock, or maybe a honed stock, injector... to prevent a meltdown. Not that he tows much if any...



FLynes and blacksheep: that's sort of my feelings too, replace it for peace of mind.



I'm sure something isn't right (and its not someting that happened overnight either) that's causing the slight power loss. If replacing these two higher mileage components will fix the issue, then its worthwhile. I'll see about cleaning the MAP and IAT next time I'm home...

 

[darkhorse]

I probably aleady know the answer to this question, but if we upgraded to the 275s, would guages be required... remember, this is a 62YO retired person, not some *kid* like myself. That would be my reasoning to stay with a stock, or maybe a honed stock, injector... to prevent a meltdown. Not that he tows much if any...



Hey I'm a 60's something retired person too & I occasionally like to lean on the go pedal. Gauges are always a good idea, even stock. RV 275's are a great bargain. If the price isn't a concern, Mach 1. 6's are even better.

 

[FLynes]

FWIW, I cleaned my original IAT sensor with carb cleaner and it came out looking new. My problem was reinstallation... 10lb/ft is NOT correct... I don't know what the correct torque spec is, but I can tell you that 10lb/ft will snap the brass fitting, and sticking your pinky in that hole to work the broken threads out will make you find God in a hurry. What I did, after I bought the new IAT was finger tight it and then I made sure that the electrical fitting sat parallel with the ground (I can't describe it any better).

 

[steved]

FWIW, I cleaned my original IAT sensor with carb cleaner and it came out looking new. My problem was reinstallation... 10lb/ft is NOT correct... I don't know what the correct torque spec is, but I can tell you that 10lb/ft will snap the brass fitting, and sticking your pinky in that hole to work the broken threads out will make you find God in a hurry. What I did, after I bought the new IAT was finger tight it and then I made sure that the electrical fitting sat parallel with the ground (I can't describe it any better).

Probably similar to the botched 40 foot/pound spec for the oil pan plug... probably should be inch/pounds

 

[cArNiVaLwOrKeR]

Steve, I am in this Thread only to get better Mileage, or ideas on how? but, I have a 4X4 LongBed, dunno if that makes a difference in my outcome, Vs 4X2 shortBox and what have you,

Im not sure if I should be happy with 17. 4 and call it a day, and never worry about it again. my G/F said that 17. 4 is great.



JoeLee

 

[blacksheepdiesel]

JoeLee,

My guess would be the Mach IIII's are not helping you as much as a 1. 5 or 1. 6 stick would. I wonder also about the 14cm exhaust housing, maybe a 13 would do better for mpg's? The 4x4 definitely takes away some mpg's too.

Godspeed,
Trent

 

[steved]

Dad's truck is a 2500 4x4, shortbed, QC, 235HP, 5spd, 3. 55s... he has averaged 21mpg on the highway, very consistantly, since new. It is completely stock, short a swiss cheese airbox, MIA silencer ring, and straight-thru exhaust (essentially free mods). He drove this truck for quite a few years, daily commuting 150 miles/day, 5 days/week. That's with a 265/75r16s. And as shown in this thread, 280k miles worth of seat time... and he tracked his mileage quite a bit, especially when the price of fuel started creeping upward... that's the single reason he retired, too expensive to drive to work.



My 99 was a 215HP auto, std cab, auto, 3. 55s, 4wd... I actually pulled 23-26mpg pretty consistantly (again, highway). The mods were similar to his. Keep in mind, I used this truck to travel cross country quite a bit... so I could be loaded with upwards of 2k pounds of equipment (in the bed). I got my best mileages with 255/85r16s (cooper discoverer LTs). I put 201k on that truck... the mileages were very consistant, and like my current truck, every tank was recorded. My city mileage was still over 18mpg.



That's two trucks, two drivers, and similar mileages... your example is one reason I have never took the plunge to modify (BOMB'd) my trucks for performance. I actually have more mods to this 04. 5 than any truck I have owned... and I can still pull 18mpg city and 21mpg highway, with 4. 10s and a 6spd. A lot has to do with the way you drive...

 

[cArNiVaLwOrKeR]

Trent,



It all began when I wanted a Truck that blew Heavy Ugly Smoke. then I got sucked into the Bombing scene, then everything went to Hell from there.



I wish I woulda never met anyone that had told me how and what I needed to do to acheive heavy Smoking



BooHooHoo.



JoeLee

 

[2-ND TIME]

With 280 K on

What is causing the dog is the injectors! Just to see that they are BAD have them POP tested they should be 4500 psi I bet that they are??? 2??0 psi. At 230,000 km mine worst was 2600 psi and peeed out of 2 of the nozzles. The RV-275 gave me the best milage but the 300's and the FEDexed vp44 helped my gutless wonder alot. There are a good engine if you get a good one!

 

[steved]

I am in contact with Lmills (mid-atlantic diesel)... going to have a VP44 and injectors installed. Just got to get home to make the appointment...



Thanks for all the insight!