Any input? 3.73's Vs. 4.10's Fluids/etc?

[Dasfinc]

I'm trading + small cash on my side my 3.73 Posi/disk rear end in favor of a 4.10 Posi/drum rear. Same # of splines, and no welding required to make the drum rear work on the ranger. *to make the disk rear I'd have to relocate the shock perches.*

I'm sure this will amplify my traction issues, but is there any recommendations for what fluid I should be running in it? I'm sure this is going to further destroy my gas mileage, but how bad should I expect it to be from those who've done this kind of gearing selection? Is the economy loss worth the performance gains?

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[Dasfinc]

Also, Is this a 'bad' idea because my truck will run out of gear too fast with a 4R70W and 4.10s? or will it not matter since I'll be lucky to trap much over 100 anyways?

 

[Eagle]

Well... big Q's here.

1st... moving perches is SIMPLE. You can buy new perches for like $30 for a set. Piece of cake to weld that junk on.

2nd... disc > drum any day.

3rd... if its limited slip, make sure to add the Ford additive to the fluids.

4th... gear ratios= 1st = 2.84 2nd = 1.55 3rd = 1 4th = .70 Therefore, assuming 28" tires, you'll top out at 118mph @ 5800RPM. More than enough gear.

5th... mileage! 4.10s will hurt. 2K RPM will only net you 58mph in 4th. 2500 = 73mph.


What you think about all that?

 

[Turbocharged400sbc]

in terms of racing id much wrather have drum brakes that i can set loose for no drag than a disk setup that drags

x2 on welding perches...pretty easy

 

[Eagle]

in terms of racing id much wrather have drum brakes that i can set loose for no drag than a disk setup that drags

x2 on welding perches...pretty easy

This is a fukkin pickup truck. Seriously worried about disc drag over every day stopping power? You so silly, James.... :rollpicard:

 

[Bob Kazamakis]

Good brakes > taller gear

 

[Bob Kazamakis]

How much you selling the 8.8 for? I've been thinking about this swap for my car for a long time. 31 splined axles and cheap gears is very ********.

 

[Turk]

Good brakes > taller gear

X2. Adding a taller gear doesn't guarantee better acceleration either considering you'll be running out of each gear a lot faster.

 

[Turbocharged400sbc]

This is a fukkin pickup truck. Seriously worried about disc drag over every day stopping power? You so silly, James.... :rollpicard:

like disks are needed for 30% of the stopping power...on the end with barely any weight...on a truck that likely isnt gonna tow anything heavy or often

i drive a truck with 4 wheel drum brakes... i can coast foreva

 

[Dasfinc]

Glad I asked this question then. .

118 is plenty and the rpms are bearable since this will not be a highway cruzer.

And I never thought about drag, that's a small but very valid point. I don't need disk at all in a truck as small as mine, it'd be more for the apperance I have to admit, so ignoring the disks 3.73s vs. 4.10s

 

[Turbocharged400sbc]

i dont think the housing ends are different so there is the possibility of swapping brakes and keeping the 3.73

just to crap on the parade some more im switching from 3.73 to 3.55 d60's in my truck but thats cause im looking for more mpg and i barely use the granny...for a fun truck i'd say go with 4.10 especially if it will be getting some big sticky tires

 

[Turk]

Glad I asked this question then. .

118 is plenty and the rpms are bearable since this will not be a highway cruzer.

And I never thought about drag, that's a small but very valid point. I don't need disk at all in a truck as small as mine, it'd be more for the apperance I have to admit, so ignoring the disks 3.73s vs. 4.10s

As I stated, having a higher gear ratio doesn't necesarilly mean your truck will be faster.

 

[Turbocharged400sbc]

i see your point but at the same time i dont see him blowing the dough on a converter or a bunch of engine mods

not to mention thats a wide gap at the 1-2 ratio

 

[cammareri1]

i see your point but at the same time i dont see him blowing the dough on a converter or a bunch of engine mods

not to mention thats a wide gap at the 1-2 ratio

Yea, the Trans is geared KILLER wide early, and I'd rather not drop the coin on a new converter, especially after getting it INTO the truck I'd rather not pull it back out.

 

[Turk]

i see your point but at the same time i dont see him blowing the dough on a converter or a bunch of engine mods

not to mention thats a wide gap at the 1-2 ratio

It's not like the rear end is going to change the trans ratios. The wide gap between 1 and 2 will remain the same.

 

[Turbocharged400sbc]

It's not like the rear end is going to change the trans ratios. The wide gap between 1 and 2 will remain the same.

no kidding, but at least it will have the additional leverage once it shifts to second, for Daily driver duty i can figure he'd be running cars from stoplight to stoplight and probably not leave 2nd for those cases.
at the track ive seen plenty of auto stangs run better times with 4.10's than 3.73's seems moreso when the motor is mostly stock. i remember going to the track when the 5.0HO stangs first came out

remember that 3inch stroke does make em winders not tq monsters

 

[Dasfinc]

no kidding, but at least it will have the additional leverage once it shifts to second, for Daily driver duty i can figure he'd be running cars from stoplight to stoplight and probably not leave 2nd for those cases.
at the track ive seen plenty of auto stangs run better times with 4.10's than 3.73's seems moreso when the motor is mostly stock. i remember going to the track when the 5.0HO stangs first came out

remember that 3inch stroke does make em winders not tq monsters

That's what I'm aiming for 'stoplight destroyer' and I've read quite a few people strongly recommend 4.10s for the auto

 

[syP]

ill run that pig from a stop

 

[Dasfinc]

I traded my 3.73 today after all. Mine was off a 96, the 4.10 was off a 05 fx1 ranger *31 spline, trac lock* and is in far better shape than mine. Done deal, almost got my pig ready.