reasonable payback on modifications

[richsaenz]

I only drive my diesel rig about 10,000 miles per year. After looking at Banks and Gearvendors and crunching the numbers, I'm looking at paybacks of five to seven years for a 20% increase in fuel economy!? Power is no problem; could I simply increase my exhaust size to help out at the pump?? 2001 E-350 7.3 PSD 4.10 gear, 80,000 miles, 8000# tt

 

[Shayne]

I believe your projections are extremely high.  It's more like a increase in mileage of possibly 4 to 10 percent.  A rare case may make it to 20%, but that would be very rare.  I have it on ours and Power yes  buying for mileage, bad deal.  Been there done that./

 

[richsaenz]

Shayne, did you go with Banks or Gearvendors? Gearvendors claims 20% increase in fuel economy for my rig. 4 to 10% would make my payback even worse! Thanks for your help!

 

[Karl]

richseanz,

This is right out of the mouth of Gear Vendors:

"There are many devices advertised as remedies for poor gas mileage. Fact is, anyone who tells you how much you are going to gain is just trying to sell you something. Every vehicle represents many different situations, different drivers, different conditions of tuning, different climates and altitudes. The GEAR VENDORS UNDER/OVERDRIVE? is not some magic pill, but twice the number of forward gears for combating all these different conditions."

Not sure where you came up with the 20% figure. ???

 

[Gary RV_Wizard]

I would be most surprised if you got anywhere near 20%  on a late model turbo diesel such as yours.  Something less than 10% is more likely, if you see any improvement at all.  Your payback will be in your enjoyment of better performance on hills (both up and down) and more responsiveness, not fuel economy.  With only 10,000 miles/year of use, the dollar payback will be long indeed.

Your actual gains, if any, will be strongly influenced by your driving habits, e.g. anticipating slowdowns and stops, gentle acceleration, etc. Managing your driving is probably the best - and cheapest - improvement you can make.

Yes, a bigger exhaust, both headers and pipes, may help a bit. But that's the major component of the Banks kit, so you are already considering that.

You should be getting about 11-13 mpg towing your trailer with a stock E350 Powerstroke, depending on terrain amd your driving. Is that what you are experiencing now?

 

[Ron]

IMHO if a dealer or any company tells you their product will get you 20% increase in fuel mileage you are better off walking away since their business integrity is suspect and they most likely cannot be trusted. If they will mis respresent the results of their product what else are they lying about??  I bet they wouldn't give you any kind of written guarantee.

 

[richsaenz]

If you go to gearvendors site under trucks/ towing and Ford 4spd , fifth paragraph down: " Expect 20% increases during highway cruising with any rear gear in the 4's and 10-15% with 3.73 with any big block gas or diesel."  It doesn't mention towing here.      I generally get around 10mpg, but my tow vehicle is also my work van(I'm an electrical contractor) so it is always loaded.

 

[Karl]

Sounds like they're contradicting themselves a little; actually a lot. However, they say "expect". Heck, you can expect anything you want. That doesn't mean they gaurantee it or that you'll even come close.

Regarding the weight issue: It shouldn't matter how much weight you're carrying. If they say a 10% increase with 3.73 gears, that's 10% regardless if you're weight is 10,000 lbs and you get 10 miles to the galllon now, or you're only at 6,000 lbs and you get 15 miles to the gallon now. One way you gain 1 mpg; the other you gain 1.5 mpg. Ten percent.