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Topic: gear/diff swap (Read 7528 times) previous topic - next topic

gear/diff swap

ok, so i grenaded the tracloc diff in my bird, apparently 7.5's dont like 6000rpm launches....i'm done racing though, just trying to get it back on the road so i can get back and forth to my new job....

i found a ranger rearend i am buying to get the gears and diff out of, it's a open diff with 4.10's, it's only temporary so i'm not worried about it not being a locking diff...i'm going to be picking up a 3.55 or 3.73 geared 8.8 in a few months, i just need my car driveable now...

my question is, what are the chances of being able to just pull the diff and gears out of the ranger case and put them in my housing using the shims from the ranger axle and everything be ok?
Currently Birdless but never Foxless

86 Mustang GT

gear/diff swap

Reply #1 –
(shaking the dice)..... come on baby.... daddy needs some gears.... :rollin:

Seriously... you might get lucky ...

I swaped out a set of 4.10's a couple months ago from a ranger also... had to change the carrier shims... man those things have gotten pricey.....

gear/diff swap

Reply #2 –
Unless it has a trac-loc, I wouldn't even bother.

Plenty of vehicles to get a trac-loc, 3.55 or 3.73 gear from...

There's a chart that explains what vehicles came with what gear ratio, and if said vehicle had or was available with the locker or not.

I thought I had it saved, but I cannot find it.

How's your google fu?
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

gear/diff swap

Reply #3 –
373's or higher are all trac loc
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

gear/diff swap

Reply #4 –
Quote from: Haystack;335327
373's or higher are all trac loc


Negative....my regular parts store had little ranger delivery trucks with a 4 cyl and open 4.10 rear
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

gear/diff swap

Reply #5 –
Sorry for the bad info, from what I have seen they have been. I have checked a couple of 4banger stangs in the junkyard, and they all were, as well as my mark 7 rear from a turbo diesel.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

gear/diff swap

Reply #6 –
well, 4.10's are in...used all the shims from the ranger rearend and everything seems to be good so far...

i cant tell ANY difference in acceleration though...i was expecting a big change, but NOPE...the gears are shorter, but it doesnt seem like it pulls any harder...
Currently Birdless but never Foxless

86 Mustang GT

gear/diff swap

Reply #7 –
Quote from: Dougy_Fresh;336011

i cant tell ANY difference in acceleration though...i was expecting a big change, but NOPE...the gears are shorter, but it doesnt seem like it pulls any harder...


Probably because your SD computer is going WTF???!!!! with the B303 cam...I guarantee a MAF swap will wake it up...but you really need a good set of valve springs to keep the valves from floating past 4500rpm too.

I'm not even trying to break your balls here.  HO springs aren't even adequate for a stock cam.  The MAF swap will bring more power in across the board due to the ability to properly and accurately meter the changes to the incoming air.  I don't even know why people buy MAF ecu's used for $125+ on the 'net, when you can get a reman unit with a 1yr warranty from most parts stores for around $100 and no core charge.

For an investment of $250-$300 and an afternoon's worth of work and some specialty tools, you could really wake your car up.

Good luck,
Don
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

gear/diff swap

Reply #8 –
Quote from: Sick88Tbird;336046

stuff


What does that have to do from going to 4.10's from...2.73's? He'd still have some 50% more torque at the wheels in all gears.

Was your old rearend stock/2.73? If it was anything less than 3.55's before, the difference would be drastic, open differential or not. You sure you have the 4.10 ratio? Count the teeth?
1988 Thunderbird Sport

gear/diff swap

Reply #9 –
Quote from: Seek;336048
What does that have to do from going to 4.10's from...2.73's? He'd still have some 50% more torque at the wheels in all gears.

Was your old rearend stock/2.73? If it was anything less than 3.55's before, the difference would be drastic, open differential or not. You sure you have the 4.10 ratio? Count the teeth?


It makes a huge difference when you have shiznit for power and aren't increasing the rev range of the engine.

You could put 5.xx gears behind a stock SO and I bet you'd be slower.  It's about the total combination...so many people miss that little fact.
Project 3G: Grandpa Grocery Getter-'85 Crown Vic LTD 2-door, 351W with heavily ported/polished GT40 heads, heavily ported/polished Typhoon Power Plus upper & lower intake, Comp Cams 265DEH retarded 1*, FAST EZ-EFI, HD T5, 8.8" 3.73 trac lock with extra clutches, 3G alt. swap, '99 CVPI front brakes, '09 CVPI rear disc brakes, '00 CVPI booster&m/c + wilwood adj prop valve.

Parted & Gone-'88 T-bird Sport, 351W swap, ported GT40 heads

gear/diff swap

Reply #10 –
Quote from: Seek;336048
You sure you have the 4.10 ratio? Count the teeth?


I'd probably have verified this before doing any work.
Just because the door code says it's one thing, it could be yet another....


And for the post regarding the reman EEC's...too right.

I'd pay no more than 110 shipped for an A9L.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

gear/diff swap

Reply #11 –
Quote from: Sick88Tbird;336054
It makes a huge difference when you have shiznit for power and aren't increasing the rev range of the engine.

That makes no sense - gearing is gearing. If you have to shift every second, sure it'll slow you down, but gearing will always speed you up in your engine's power band. Now if your motor runs out of steam at 4000 rpm's and you're already in your 1:1 transmission gear, yes you'll slow down above that but everything below will have a huge performance improvement with 4.10's over 2.73's.

Quote from: Sick88Tbird;336054
You could put 5.xx gears behind a stock SO and I bet you'd be slower.

It'd still be quicker (with traction) in all gears - you'll just run out of power sooner as you use up all the gearing.

Also, what are you claiming would be "slower"? Quarter mile? I would agree that with a stock 5.0 SO revving engine would only benefit from about 3.55's with an aod and 3.31's with a t5 - if I remember right, the stock SO 5.0 does die off at 4k, although with my old tired one, it felt like it fell apart at 3.5k.

In the 1/8, 4.10's would work much better, with traction.

His 4.10's should have a huge seat-of-pants feel improvement.
1988 Thunderbird Sport

gear/diff swap

Reply #12 –
Quote from: Seek;336063
His 4.10's should have a huge seat-of-pants feel improvement.



+1 on this 
 With no other changes at all, a gear swap should make a huge difference in seat of the pants feel .
 Greater torque multiplication gets the car moving more quickly period.
 Of course we still dont know what he was running for gears before the swap
Fox-less at the moment

gear/diff swap

Reply #13 –
If you've ever driven a stick shift car, this should be obvious. try starting out in second, then start out in first. If you really ride the clutch, you might not be able to tell any difference, but if you get it to 5mph and let the clutch go, I am sure first gear would be quicker.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

gear/diff swap

Reply #14 –
i had 2.73/tracloc before, 4.10/open now...

it runs good and pulls hard up to 6000rpms, it just doesnt seem like it accelerates any faster than before....wierd thing is it still hooks up...i just launched it at 4000rpm's in first and it only spun for a split second and it hooked and took off...
Currently Birdless but never Foxless

86 Mustang GT