honest opinion

[wedge44]

OK here's the question:
Gear Change or Engine Upgrades or Both
I have 2006 F-350 Crew Cab w/ 6" Fab-Tech & 325/60 R 18 Nitto A/T STOCK Motor, I pull a 2006 Wildcat 28 Rk 5th wheel & 2003 Ultra 23XS Combined weight 11,000 # RV....5,000# Boat
recently I've pulled 2 ways for comparison, with stock and with the 35's, mileage and hill pulling as follows: I towed from Santa Clarita to Don Pedro, so the only little hill I hit was the grapevine and it went like this;
going north with stock tires: pulled G/V at 53 MPH and averaged 13.8 MPG
going south with stock tires; pulled G/V at 50 MPH and Averaged 13.5 MPG
going north with 35's; pulled G/V @ 48 MPH and averaged 9.8 MPG
going south with 35's; pulled G/V @ 45 MPH and averaged 9.7 MPG
I tryed to keep PRM same for both pulls I didn't want to push high RPM i keep it @ 3000 RPM and tranny selected gear. lower gear for the 35's little higher rpm.....
So change out gears front & rear or chip it With Exhaust etc.....
Now accepting all comments .....thanks Wedge
And one more thing......Chevy people SAVE-IT

[wedge44]

wow no ford people with an opinion on this subject.....chevy people SAVE IT

[ryantparks]

gears wont void your warranty right? Niether would exhaust but a chip would.
Gears and exhaust. Going w/o the cat would also lower your egts but for any dealer warranty issues the cat would have to slip back on.

[cc322]

You have no other choice... to get it back correctly you need to do the gears. Exhaust wont void warranty, but chip will if they can detect that a failure was caused by the chip. Check these guys out for the gears they are highly recommended. http://www.gounitrax.com/default.htm I have a 03 f250 with the V10 stock gears were 3.73, now with the 315/70/17 I will be going to a 4.30 V10 and 4.30 the truck moves fast, been in enough of them that have had it done. It's about a 1,400.00 to 1,500.00 job

[Sleek-Jet]

Why don't you want to wrap it up a little on the climbs???
From what I've been around the Ford V-10's, they like their RPM's... don't know what the redline on them is, but I'd go ahead and run it up a little, shouldn't hurt anything.

[wedge44]

my o2 was f-350 v-10 with 4.30 loved that truck too bad it had tranny leak ford could not rid of till after 3 rebiulds and a swap ...lemoned it went with 6.0 diesel love the power just now getting used to the turbo lag, miss that off the line power of the v-10 but the love the torque pulling of the diesel ,,,so now question 4.10 or 4.30 gears .....?

[The Real Kings Biggest Fan]

Be careful with the chips. My 2000 with 35s, 120 hp superchip and too much loud pedal up hills burned the turbo with just a 21 ft ultra. And that is with no exhaust after the down pipe. I would ask a shop for the right gears to return 35s to stock ratio and then use a performance package that adresses egts. you need a big exhaust and intercooler to turn up a deisel and keep the turbo cool. Water/methanol injection helps as well as small amounts of nitrous. you can also checkout cryo2 systems to fog the intercooler on big grades like gv. but don't just chip it big and tow or itll cost you in the end.

[cc322]

If you have 3.73 then going to 4.10 dosent make much sence, go 4.30 or 4.56. Call the phone number at the link I provided they will tell you what is the best.

[wedge44]

Thanks for the input ....Iwent and did calculations on thier site and it shows I shouls goto 4.351 ratio or 4.3....that's what I had on the v-10....I just thought it might have been a little too low.....wedge

[MBMOSEBILT]

I Have Posted Many Times On All Different Sites. Leave It Stock And Run It To The Ground. You Never Herd Your Grandfather Tell Story's About His Lifted Super Truck Last 140,000 + Miles With Just Maint.

[cc322]

I Have Posted Many Times On All Different Sites. Leave It Stock And Run It To The Ground. You Never Herd Your Grandfather Tell Story's About His Lifted Super Truck Last 140,000 + Miles With Just Maint.
Now thats boring :rolleyes:

[springerpete]

Put a 4" exhaust and a free flowing airbox on it. It will pick up mileage and power. The larger exhaust will cool down the turbo and cure some of the lag.
If I am thinking right you can buy a speedo recalibrater. It can either be a stand alone or in programmer version.
The only way they can detect that a chip has been on your truck after you remove it is that the chip allows the engine to build more boost than the factory specs. That will show up on the engine history in the computer. If you use the programmer to only recalibrate the shift points and the speedo it shouldn't affect your warranty. But I would still take it off before you took it in for work.

[HMF'er]

When you did your stock vs. big tire comparison, did you account for speedo error? With those size tires, you should add between 8 and 10 % for speed and mileage if the speedo was stock.

[wedge44]

calculations were done using the 3000 year old method....wedge

[HMF'er]

A more advanced method.
Try this. (http://www.1010tires.com/TireSizeCalculator.asp)

[springerpete]

I have a Edge box with an Attitude monitor. The monitor controls the power levels. It also acts as the gauges for the truck. It will monitor 4 functions at a time. I own a Duramax,
Maybe this will help
http://www.edgeproducts.com/ford_60_powerstroke.html
I will say do the exhaust first. You don't want to add extra boost without improving the exhaust flow. That will raise EGT's and burn up your turbo. If you have a good muff guy and you want to keep your converter he should be able to cut it out for the 4" exhaust. That way it won't void your warranty.
My brother has a muffler shop and diesel performance business.