I'm in a major dilema here folks... I've shopped the trucks and have decided to order a new supercrew, but am a little pissed about the wheel options available WRT towing. I've had two lariat SuperCab F150s now (a '97 and '98) and now love the leather interior... the problem is that if you get the supercrew optioned as a lariat- you are stuck with the 17" wheels and tires. What's the problem with that? It drops the gross trailer weight down 500lbs to 7200lbs (for the 4x4 with 5.4, which is what I'll be getting). I'd really like to get the lariat package for the leather, and be able to option the 16" 5-spoke cast aluminum wheels and LT tires. Tough decision now.

It may be possible to go to the expense of changing out the 3.55 front and rear differentials with lower 3.73 or 4.1 gears which would certainly bump the towing performance back up. Has anyone done this here with the monster 5.4 differential? Can the speedo be recalibrated properly?

Thanks for any help guys... this is killing me.
jC. www.lugnutz.com

 

What are you towing thats going to max the rating. If you are border line on the max towing cap. You should consider the SuperDuty....

I tow a 22ft 4500lb Boat with a very tired `88 Bronco. Does the job fine. Anything heavier I'd want a longer wheel base for longer trips and bigger truck for more stopping power. Remember Newton's Law on Motion.....

 

It's about 3000 lbs worth of camaro, 3300 lbs worth of a lightweight enclosed trailer... and a few hundred pounds of gear and passengers.

Believe me, I tried several superduties, the 2500 Sierra, etc and the decision wasn't easy. We only go racing maybe 20 times a year, and I have to drive this truck every day in my commute- so that made the decision pretty clear. Not to slam the SD, but the ride and turning radius, etc just aren't even in the same ballpark as the F150. I just wish there was a little more margin in the tow capacity.

Stopping by the dealership tonight, I measured the two different tires- the 16" P255 tires for the XLT and the 17" offroaders on the Lariat. The difference? Approx 29.25" diameter on the 16s and 31.25" on the 17s. There's your 500lbs of towing capacity. The ratio difference is almost the same as the 3.73 gear change from a 3.55 (1.4%). (i.e. you might get by reprogramming the computer after changing over to 3.73 by telling it that you have 3.55 with the shorter tires.) My sales guy is going to talk to the service dept tomorrow about gear changes and speedo reprogramming. Will let you guys know if anyone is curious?

jC.

 

jcakers, I'll bet if you ask, someone out there would love to trade their 16's for your 17's.

 

Heh heh, yeah that's what I figured.

jC.

 

jCAkers,
First of all, you shouldn't be towing a Camaro with a Ford. Thats what you're problem is. Put a Mustang back there and it'll be like having a 4:11 rear end.
BTW if you need tire diameters, you don't need to go to the dealer; check out:http://www.powerdog.com/tiresize.cgi
If their calculations are correct, the Lariat's 265/70R17 tire(31.6" diameter) is 5.2% greater than the 255/70R16 (30.1" diameter); and you're absolutely correct in that your 3.55 ratio becomes an effective 3.73 with the 16" tires. I think the cheapest alternative, if you can't get someone to swap your wheels & tires is to change your tires to a 275/60R17 with a 30.0" diameter. For about $600 you should get the same results. When I tried to get the diffs. changed in my '90 Bronco (for the exact same reason-but with a different car in the trailer!)I was quoted a price over twice what you'll pay for tires. I'll bet the dealer or a tire store may swap you even as long as the tires are new. They should throw in the mounting and balancing since you're giving them bigger tires. Keep us posted and good luck.

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2001 SuperCrew, 4x4 Lariat, Blue/silver, 5.4L Captains Chairs, 3.55LS, Moon roof, everything but the Bed extender & AV system.(Ordered 2/11/00, Order on "Temporary delay" 2/29/00)

Planned Mods: Sprayed-On Bedliner-(LineX or Rhino); Hard tonneau-(*******, ARE or Snugtop); Fiberglass Cab steps (Ford) or SS nerf bars; Gibson SS Dual Sport Cat-back system; SuperChip; K&N Air intake kit; Clear back-painted bug-deflector; SVT Lighting wheels and Michelin Pilot LTX 285.60/HR18 tires.


[This message has been edited by SuperCrew (edited 03-08-2000).]

[This message has been edited by SuperCrew (edited 03-08-2000).]

 

heh heh, IMO I get the best of both worlds- the best truck and the coolest car to pull.

Thanks for the link... but I have to disagree. Tire mfrs are notorious to "approximating" the numbers (like a 5.0 mustang) when they designate tires. The only real way to know exactly what a given tire is - is to measure them yourself. This goes for everything from racing slicks to street tires. (and is evident in the different numbers I measured and the numbers you posted)

BTW, I still haven't heard back from my salesguy with a number. I thought about it some more and believe maybe you could use the Abbot ERA box that is popular for gear changes with the late-model mustangs. If this would work, I'd probably step up to a 4.1 gear. According to my calcs and the measured tire diameters, with 4.1 gears and the 17"ers, you'd still only be turning 2178RPM at 70mph in overdrive.

Lato!
jC. www.lugnutz.com
'67 Camaro - 8.94@150
'98 F150 4x4 SC Lariat 5.4 - 16.46@82
'00 Mustang GT 5-sp - 13.87@100
'01 SuperCrew 4x4 Lariat 5.4 on order!

[This message has been edited by jCAkers (edited 03-09-2000).]

 

Supership your Supercrew! That's a lot less expensive than swapping rear ends. That extra torque and HP ought to give you back your lost 500 lbs.

 

That's Superchip, not Supership. Fingers and brain not connected Although, I'm sure someone can come up with a coll meaning for Supership.

 

Forget it. I simply cannot type today.

 

Frankly, I'm not convinced of the value of a SuperChip (hope I don't get branded as a heretic) since I haven't seen anyone post real dyno numbers or track times before/after. Also, since this is my daily driver, I like to run the cheapest gas I can during the week... and the thought of paying $1.80/gal for premium for my truck gives me the heebeejeebees.

I did pick up about 10-14 net HP (based on actual track times) from changing over my '98 F150 to a dynomax cat-back, so that will be one of my first mods. (It sounds better than the stock puffler too.) I ASSume since the SupCrew is based on the SC chassis that my exhaust my swap right over.

jC.

 

jCAkers,
I do agree with you that the Mfg.'s stated size can vary from the measured diameter. But how do you get a true tire diameter measurement with the tire mounted and on the vehicle? Seems to me there are several variables that will affect the measurement, namely the air pressure and the load. Do you measure the radius from the center to the top for example?
Excuse my ignorance, but what's an Abbot ERA box? (I'm not changing anything on the Bronco since it only has to last until the S-Crew arrives.) Soon, I hope.

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2001 SuperCrew, 4x4 Lariat, Blue/silver, 5.4L Captains Chairs, 3.55LS, Moon roof, everything but the Bed extender & AV system.(Ordered 2/11/00, Order on "Temporary delay" 2/29/00)

Planned Mods: Sprayed-On Bedliner-(LineX); Hard tonneau-(*******, ARE or Snugtop); Fiberglass Cab steps (Ford) or SS nerf bars; Gibson SS Dual Sport Cat-back system; SuperChip; K&N Air intake kit; Clear back-painted bug-deflector; SVT Lighting wheels and Michelin Pilot LTX 285.60/HR18 tires.

 

The absolute best way to measure them on the vehicle is to mark the tire and ground, then roll the vehicle until you get a full revolution- that's the real circumference. I did the Next Best Thing (tm) which is to measure across the tire where it's the least deformed (i.e. level side-side).

Here's a link to the ERA box: http://www.atrol.com/cx_era.htm

I've used the old cyberdyne equivalent to this (which was pretty much junk). I've heard good stuff about the era box... friend of mine used one in his '99 cobra when he changed over to 4.30 gears... so it will probably work for the new trucks as well. It's worth a shot!

jC.

 

Do you really need the 4WD in Raleigh? The brochure states that the max. trailer weight goes to 8000 lbs in the 2WD w/o a penalty for the 17" wheels.

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2001 SuperCrew, 4x4 Lariat, Blue/silver, 5.4L Captains Chairs, 3.55LS, Moon roof, everything but the Bed extender & AV system.(Ordered 2/11/00)

Planned Mods: Sprayed-On Bedliner-(LineX); Hard tonneau-(*******, ARE or Snugtop); Fiberglass Cab steps (Ford) or SS nerf bars; Gibson SS Dual Sport Cat-back system; SuperChip; K&N Air intake kit; Clear back-painted bug-deflector; SVT Lighting wheels and Michelin Pilot LTX 285.60/HR18 tires.

 

yes. Although the 20" of snow we got 6 weeks ago wasn't typical, there are other things to do around here that just about require a 4x4... like pulling boats out of the lake, going 4-wheeling in the mountains, cruising around on the beaches of the outer banks, etc.