Johnny50

It was. Remember, I'm still using stock wheels and tires. I believe the wheel speed sensors are used for speedometer not the transmission tailshaft like pre 15's.
Maybe that's why Ford can't correct with IDS like the older trucks anymore.

D2Abbott

I read into the service manual and it doesn't make sense that a speedometer would not be effected with a gear change, it should be. Indeed, as typical to most vehicles, a transmission output sensor is utilized.

From the manual:
Power Control Module - Vehicle Speed Output (PCM-VSO)
The PCM-VSO speed signal subsystem generates vehicle speed information for distribution to modules and subsystems that require vehicle speed data. This subsystem senses the transmission output shaft speed with a sensor. The data is processed by the PCM and distributed as a message on the vehicle communication network....

bcb97

Sounds like you could do a really nice write-up directional on how to for this swap!

Johnny50

I read that as well and was fully expecting to have to get a speedometer calibrator to complete the job. Maybe once others start changing out gears, we'll have more input on the subject but for me at least, my RPMs are about 200 - 250 higher than before at the same highway speed with +-.5 km/h accuracy in speed measured by GPS to speedometer. I'm not saying I'm correct in all this, I just believe the evidence I have leads me to think so. For me the GPS was what confirmed it.

acdii

When I replaced the stock 18" wheels and Goodyear LT's with 20" Bridgestone Duellers off my 14, I fully expected to have to recalibrate as well, but the speedometer is dead on to GPS. I double checked the two tires and they are not the same revs per mile, so how do it KNOW! When I put the 17" snows on the 14 in place of the 20's I had to recalibrate it quite a bit.

OK, wild guess, auto calibration via GPS! Yeah, thats it, sticking to it.

msgtord

actually it makes sense. The speedometer in my truck is the most accurate of all of the ford's I've owned.

ABolt

Great write-up and interesting info. Looking forward to following this thread.

So $350 CAN is about $250 U.S. If I had the know-how, I'd do this TODAY! Unfortunately, most quotes I've seen for such a gear swap come in around $1,000 per axle, which I just can't justify...

acdii

That is a good price for gears. I was going to do a swap on my 14 from 3.15 to 3.55, and add a TruTrak, and could not find 3.55 gears anywhere near that cheap! For what I was looking to do the parts would have been over $1200 for one axle.

Johnny50

Torque Specs
Front Axle
front driveshaft CV joint to pinion flange cup bolts and retaining straps.Torque: 41 lb.ft (55 Nm)

wheel hub nut Torque: 30 lb.ft (40 Nm)
wheel speed sensor wire bracket bolt Torque: 106 lb.in (12 Nm)
flexible brake hose bracket bolt Torque: 22 lb.ft (30 Nm)
IWE bolts Torque: 106 lb.in (12 Nm)
outer tie rod end nut Torque: 85 lb.ft (115 Nm)
upper ball joint nut Torque: 46 lb.ft (63 Nm)
Measure the depth of the CV shaft threaded end to the inner bearing race (shown in illustration). The
minimum depth is 15.5 mm (0.61 in). If the depth is less than 15.5 mm (0.61 in) rotate the CV shaft to clear a
binding condition between the IWE and CV splines.
crossmember nuts and bolts Torque: 66 lb.ft (90 Nm)
axle tube bushing bolt and flagnut Torque: 111 lb.ft (150 Nm)
rear axle housing bushing bolt Torque: 111 lb.ft (150 Nm)
front axle housing bushing bolt Torque: 129 lb.ft (175 Nm)
Install the remaining new ring gear bolts. Torque: 94 lb.ft (128 Nm)

differential bearing cap bolts. Torque: 77 lb.ft (105 Nm)

differential pinion shaft bolt. Torque: 22 lb.ft (30 Nm)



front differential fill plug. Torque: 18 lb.ft (25 Nm)

PREMIUM SYNTHETIC HYPOID GEAR LUBRICANT XY75W85QL 1.66L (3.5 pt)
Item Specification
Backlash Specifications
Ring gear backlash 0.204-0.305mm (0.008-0.012in)
Ring gear maximum backlash between teeth 0.101mm (0.004 in)
Clearance Specifications
Differential case maximum runout 0.076 mm (0.003 in)
Housing spreader adapter thread engagement 12.5 mm (0.500 in)
Maximum differential housing spread 0.762 mm (0.030 in)
Lubricant Fill Level Checks
Lubricant level 9.56 mm (0.38 in) below bottom of differential housing fill hole
Rotational Torque Ranges
Pinion bearing torque preload 1.8-3.3Nm (16-29 lb-in)

Rear Axle
Install the remaining new ring gear bolts. Torque: 94 lb.ft (128 Nm)


wheel speed sensor bolt and position aside the wheel speed sensor.Torque: 133 lb.in (15 Nm)

differential pinion shaft locking bolt.Torque: 22 lb.ft (30 Nm)

differential bearing cap bolts.Torque: 83 lb.ft (112 Nm)

NOTE: When installing the drive pinion flange and pinion nut with no differential carrier installed, the drag torque(torque to turn) should be 2 to 3 Nm (16-29 in lbs).

driveshaft to pinion flange bolts.Torque: 76 lb.ft (103 Nm)

differential housing cover stud bolts.Torque: 33 lb.ft (45 Nm)

General
Specifications
Item Specification
Available drive pinion bearing adjustment shim in steps of 0.025 mm (0.001 in) 0.3811.219 mm (0.010-0.038 in)
Maximum axle shaft flange runout 0.076 mm (0.003 in)
Maximum differential case ring gear flange runout 0.076 mm (0.003 in)
Maximum pinion flange runout 0.279 mm (0.011 in)
Pinion bearing rotational preload 1.83.3 Nm (16-29 lb in)
Ring gear backlash 0.203-0.304mm (0.008-0.012 in)


PREMIUM SYNTHETIC HYPOID GEAR LUBRICANT XY75W85QL 1.93L (4.0 pt) (to the
bottom of the filler hole)

carrierj

Using FORScan you can set your gear ratio in the BCM.