Regearing F-150

[85_Ranger4x4]

My dd is a 2002 F-150, 5.4, 4R70W automatic trans, 3.31 gears and 255/75-17 BFG MT's (32" tires per TRS tire calculator)

If you can see the problem with this setup give yourself a pat on the back.

Anyway, the truck is a dog around town and gets it butt kicked on hills on the highway, TC lockup is touch and go at interstate speeds (70+) with any kind of a headwind. Living in a small town with a V8 Ranger to get my kicks on it hasn't been a big deal, but I am hoping to buy an acreage in the near future about 7 miles out of town...

When I first got the truck it came on 235/70-16 AS tires, it gave the truck the look of a hippo trying to ride on a roller scate and being P rated they had no business IMO of being on a truck of any size let alone a half ton...

I like to do some pulling (two round bales on a car trailer or a tractor) I have been switching back to my old 255/70-16's when I need to move something heavy which is a PITA. The trucks that rocked similar size tires (265/70-17) from the factory had 3.73 gears.

Question is, while I am at it... should I go with 3.73's or 4.10's?

 

[projectnitemare]

Depending on how much you tow, the distance and weight 4.10s might not be a bad idea but you'll sacrifice milage. 3.73s aera a good all around gear and you'll notice a jump going from 3.31s to these for sure. Either ratio would be a good choice. If you are towing a good bit I'd say the deeper ratio would help you, if not go witht the 3.73s.

Matt

 

[alwaysFlOoReD]

Also if you are using a taller than stock tire 4.10's would be better. I use 4.10 in my b-II with 31" tires and my speedo is 5% off. Originally 3.45

Richard

 

[shane96ranger]

Based on my experience, I would go 4.10's. I have 265/70-17 tires (31.61") and 3.55's... but as you know, I have the 4.6 instead. Mine does "OK", but if it gets any wind resistance, it keeps downshifting to gain speed.

One question though.... I thought the 5.4's had the 4R100 in 2002?

 

[85_Ranger4x4]

Based on my experience, I would go 4.10's. I have 265/70-17 tires (31.61") and 3.55's... but as you know, I have the 4.6 instead. Mine does "OK", but if it gets any wind resistance, it keeps downshifting to gain speed.

One question though.... I thought the 5.4's had the 4R100 in 2002?

My brother has a '97 with the 4.6, with the same set up as yours (except std cab longbox) and it was pretty much the same as mine is right now. He went to 4.10's and is thrilled with it... which is what swayed me from 3.73's to start with. 4.6s like a little more RPM than a 5.4 too (kinda like a 3.0 to a 4.0)

Only the F-250LD, F-150 7700 and Lightning got the 4R100. Aside from the Lightning they also got the goofy 7 lug wheels and 10.25 rear axle. Mine just has the 9.75 rear axle and 5 lug wheels and sure as heck ain't no Lightning

 

[85_Ranger4x4]

Since my tires are less than half an inch bigger than OEM, I am really leaning to 3.73.

I found this nifty calculator in the tech library I had never seen before, according to it a 3.65 gear would restore my factory tire/gear ratio... so in reality 3.73's would be deeper than what my truck was with the factory donuts.

http://www.therangerstation.com/tech_library/Gear_Tire_RatioChange.html

 

[adsm08]

Eh, the 4R100 isn't so special. It's just Torqueshift guts crammed into a 4R70 case.

3.73 gears should make you happy enough.

 

[85_Ranger4x4]

3.73 gears should make you happy enough.

I hope so, I have two sets setting by the deep freezer waiting for a window to open.

 

[85_Ranger4x4]

I finally got the rear done.

At first I noticed a big difference, it just feels so natural though it doesn't take long at all to get used to it and reset it to the new norm.

I can't wait to get the break in period over with so I can actually get on it hard though.

 

[shane96ranger]

Break in period? First thing I did was test my 3.55's on my Mustang... I'm talking maybe one mile on them. Never knew there was such a thing.



Sent from a Commodore 64 using a 300 baud modem

 

[Snoranger]

Break in period? First thing I did was test my 3.55's on my Mustang... I'm talking maybe one mile on them. Never knew there was such a thing.

My old Mustang 3.73 break in procedure:

-Back out of shop.
-Place shifter into 2nd gear. (while still rolling backwards.)
-Rev engine to approx 5000 RPM.
-Side-step clutch pedal.
-Powershift into 3rd gear and ride it out till the tires stop spinning.

 

[85_Ranger4x4]

Break in period? First thing I did was test my 3.55's on my Mustang... I'm talking maybe one mile on them. Never knew there was such a thing.

Instructions said 500 miles of easy driving of varying speed, no costanstant high speed or towing.

 

[shane96ranger]

My old Mustang 3.73 break in procedure:

-Back out of shop.
-Place shifter into 2nd gear. (while still rolling backwards.)
-Rev engine to approx 5000 RPM.
-Side-step clutch pedal.
-Powershift into 3rd gear and ride it out till the tires stop spinning.

There we go. That's a great procedure. This should be printed on the side of the box.

 

[Snoranger]

There we go. That's a great procedure. This should be printed on the side of the box.

That was the same procedure I used on:
The new clutch.
The used trans.
The new clutch cable.
The new rear tires.
The front brakes.


You get the point.... I even used this procedure to break in the new oil after every oil change.

 

[shane96ranger]

My old Mustang 3.73 break in procedure:

-Back out of shop.
-Place shifter into 2nd gear. (while still rolling backwards.)
-Rev engine to approx 5000 RPM.
-Side-step clutch pedal.
-Powershift into 3rd gear and ride it out till the tires stop spinning.

That was the same procedure I used on:
The new clutch.
The used trans.
The new clutch cable.
The new rear tires.
The front brakes.


You get the point.... I even used this procedure to break in the new oil after every oil change.

Can someone make this a sticky?