4 speed to 3 speed - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

SiX_iN_a_RoW · 09-28-2002, 14:00

Well got my 4 speed Auto service today and it is much better to drive. The only problem is it ocassionally flares while changing gears etc and it doesnt like reverse all that much.
The transmission guy reckons that the seals have gone hard inside the box and would require a reco'd box in 6-12 months time.

In the meantime I plan to nurse the gearbox but I thought I'd throw this question on the forum to see what happens.

How much would a 3 speed Auto go for...both second hand and reco'd?

What EXACTLY needs to be changed?

Tail shaft ( shorter or longer?)
Auto Computer?
Centre console ( heheh no big deal )

what else would be involved in the conversion? and how much do you think it would cost all up......by doing it myself or paying a mechanic?

And before anyone suggests to put a T5 in it, let me say this....I upgraded from a 4 speed escort and I am SICK of changing gears.....I do 1200km's a week and I'd prefer an Auto.

Any help appreciated

Troutman · 09-29-2002, 23:34

The 3 speed transmissions themselves cost only a few hundred for a good one. They don't rely on the computer for operation so I'm not sure if you'd need to replace the computer.

Don't forget that performance, economy, smoothness and highway drivability will all be severely compromised. Perhaps finding a good secondhand 4 speed is preferable.

MightyEFGhia · 09-30-2002, 01:26

Arent the ratios in 1st, 2nd and 3rd the same for both the 3 speed and the 4 speed?? in that case performance wouldnt be comprimised, but a bit of cruising economy may be the down side to it

MightyEFGhia · 09-30-2002, 01:28

Oh yeah, without hogging posts, just to add, if you want a 3 speed, get a really good one, I was looking at a C4 conversion that was pretty well worked up, the full conversion was only $1500 and it wasnt even computer controlled, so I thought that was pretty much worth it. Pity I dont have any money now since Ive dropped an ED 4.0 into my NA haha

FastFords · 09-30-2002, 01:57

i'd be sticking to a 4speed, i have a 3 speed in my ea and off the line the thing doesn't move. I also have heard that the 4sp & 3sp ratios are the same but i was recently eaten by a 4sp Ea so i dont really think that this is the case. my 3sp sits a 2450rpm at 100km/h, how i'd love another gear....
I'm currently trying to get rid of my 3sp

SiX_iN_a_RoW · 09-30-2002, 02:13

Well how much were you looking at selling the box and accressories for FastFords?

The 4 speeds are quicker off the mark because of the short diff ratio and smoother gear changes.

I may have gotten onto someone who can repair my 4 speed for around $500......might look into that a little further as I love the idea of the 4th gear since I live in the country and am constantly sitting on 100+ k's.

Anyway I'll have to wait and see what happens....

MightyEFGhia · 09-30-2002, 07:34

your 3 spd got eaten by an 4 spd EA?? my NA 3 spd ate an EA 4spd... ah well, i spose its what you like, i have no probs now that i have a 4.0 donk, she gets up n moves, i think most of your problem is that it has a 3.9, and when compared to the 4.0, the 3.9 is rather average

FastFords · 09-30-2002, 22:54

about $400, i have just repleced the gasket cuz it was leaking a little. MightyNA 4L a a big help but then again a mate of mine get hi 14's out of his 3.9. I was eaten from standstill to 130k's, 3 speeders are pretty much hopeless of the line unless u can afford 3.23 or 3.89 ratios and a higher stall conv, personally i'd be looking for a manual!

SiX_iN_a_RoW · 10-28-2002, 21:59

Someone just told me that I will have to change the ECU to that of the 3 speed EA if I convert from 4 speed auto to 3 speed auto...is this correct or will it be ok just to remove the 4 speed computer and retain the original ECU?

I still dont know EXACTLY what I need to change....
All I know is that the tailshaft will need to be changed...I will need the kickdown cable setup off the donor EA, the box itself...the Console ( cosmetic reasons only ) and Im guessing the trans mount too....anything I should add to the list?

CATman · 10-29-2002, 01:36

y dont u go to a wrecker and c how much u can pick up a 4 speed for??? would be well worth it, and I wouldn't really bother wif a 3 speed. I dragged a ea fairmont mpfi, that had head work and a 3 speed, my car is just a mpfi, EF manifold and 4 speed, I pulled about 2 or so car lengths ahead by the time I got to 80kms. so do your self a bit favour and get a second had 4 speed.