This is topic AOD 3.73 vs 4.10 in forum Tech Talk at Northern California Ford Owners  .


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Posted by 9165pt0 (Member # 7625) on :
 
I know most of the talk out there, is to gernerally go 3.73s with t5 and 4.10s being the equivalent for an AOD. But looking for any real life experience from ppl who have had 3.73s in an AOD car. Hows the driveability compared to 4.10s?
 
Posted by 83notcher (Member # 12608) on :
 
Im wonderin the same thing. Im swaping out my 3.55s for 4.10s mine is goin to be strip only
 
Posted by 9165pt0 (Member # 7625) on :
 
im def interested in what you think about the switch. I hear 3.73s to 4.10s is just a couple hundred rpm difference and 4.10s are best. but if 3.73s provide decent performance gain, it maybe better for a car that sees the hwy.
 
Posted by 9165pt0 (Member # 7625) on :
 
hey idk where your getting your gears installed. but I have heard good things about 2 local guys, blown95svt and sacstangdriver. if you haven't already contacted them
 
Posted by 90 7up lx (Member # 10304) on :
 
In my ssp I had the 3.08 swaped out for 3.73s. With shortys or h pipe and electric fan I got 14.5 1/4 MILE ET.

I had no problem with the 3.73s as my daily...but if I we're to do it again I would go to a 3.90 or maybe even a 4.10

Dnt fear the gear
 
Posted by 83notcher (Member # 12608) on :
 
I was thinking about doin the swap my self but if i could get someone to do it rite the first time for a decent price then ima shoot for that. Thanx for the referrals ill try contacting
 
Posted by fredfifty (Member # 10320) on :
 
i have 4.10s with an AOD and i have no complaints, i could DD it if i needed to...i also have a stall and shift kit, so that helps i guess...
 
Posted by 83notcher (Member # 12608) on :
 
what about 4.10s on a 5 speed anybody?
 
Posted by 9165pt0 (Member # 7625) on :
 
1st gear in a 5speed with 3.73s can take a lil getting used to. id bet with 4.10s its really short
 
Posted by 83notcher (Member # 12608) on :
 
ill prob eventually go to a c4 trans so im just goin to go with 4.10s since the car sees zero street miles just 1/4 mile runs
 
Posted by 90GT510 (Member # 9199) on :
 
its all personal preference they say 355 for freeway but I got 373s and it does just fine driven it half way across the country and daily drive it.

im sure 410 would be good too but will hurt fuel economy in streets maybe hwy too idk
 
Posted by 2T0NE (Member # 4216) on :
 
4.10s t5 or auto ftw
 
Posted by nitrous_bob (Member # 77) on :
 
i use 4.10's in my T5 cars, cuz.......go 10 or leave it stock IMO

your looking at about a 1/4 MPG difference int he 2, but the torque multiplication means everything.

i had 3.73 in a AOD '90 GT , still bogged. gt40 intake , wide gear set , a few bolt ons.... ran 14.40's


i had 3.73 in a '90 AOD 'vert, it needed every bit of it to break loose on wet pavement. it ran 15.10 on motor and 13.60 on a dry zex 100. i guarantee the car would have been a .5 faster on motor and 4.10 , because 100 shot should only gain a second....not 1.5

also the diff is literally between lifting a tire and NOT lifting a tire on a bone stock motor modded correctly

for fuel mileage look at this way. you'll run 250 rpms lower with 3.73 than 4.10.

so get the 10's and slow down 5 mph everywhere you go....and your mileage wont change

ive been playing this 5.0 game since august 1990, and if you count a 289 then back to 1988

TRUST me when i say.....go 4.10 or leave it stock. you will be HIGHLY disappointed with 3.73 in an AOD car

****disclaimer*****

i already know someone is gonna say "your crazy, i did 3.55's and it was way better than stock"

well guess what ?????

a rotted big mac from the trash is delicious to a starving ethiopian too....but that doesnt mean its really all that good to eat does it ?

my SLOWEST bone stock T5 car was faster than my fastest T5, and thats due to 1 thing primarily:

GEARING
 
Posted by nitrous_bob (Member # 77) on :
 
quote:
Originally posted by 90GT510:


im sure 410 would be good too but will hurt fuel economy in streets maybe hwy too idk
ah yes.. the infamaous
"use 3.73's youll get 27 mpg, but if you go to 4.10 you'll drop to 8 mpg"

^^^^ read what i said about 250 rpms, thats it

FYI, a 4.10 5.0 in OD or 5th will tach 3000 doing about 80 mph
and no...you wont have to shift into 5th in the 1/4 mile.
a stock/mild cammed car will cross the traps at about 5200 with a 26" tire and 4.10's

which is ??????? say it ?????

PERFECT !
 
Posted by 9165pt0 (Member # 7625) on :
 
^^^ very good info, esp from personal experience. I suppose higher rpms and less gas mileage will still occur with 3.73s. so performance wise it seems smarter to just go with 4.10s and atleast enjoy the performance of the gear swap.

question, nitrousbob, with 4.10s what mph did it shift into od during normal driving?
 




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