SaabCentral Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
3,932 Posts
Discussion Starter · #1 ·
HI guys ,

Is the Auto coupled to a 1995 V6 the same box that would be coupled to a 93 2.3 4 Speed auto ? Both cars NA if that makes any difference .

I am guessing it is , but would like to confirm as I am looking at a V6 that may become a handy parts car .

Thanks

Les
 

·
Registered
Joined
·
253 Posts
The shortest answer is no :cry:

Bolt pattern of the bell house is different, axles are different, internals are different.
The first two issues could be solved (changing bell house and axle studs) but the third is a different story.
All autoboxes are matched to a specific engine, torque characteristics being the main factor here. Needless to say the V6 has a very different torque curve from your engine. So even if you would be able to make it fit, it will shift and drive like crap.

Your best option is to find a box with the same GA.... number as your present one. Or fix it, what's wrong with it anyway?

Later (94-) boxes have a FA... number and will not fit either, Saab changed the bolt pattern in 94. However a post-94 box for a n/a 2.3 will fit if you exchange the bell housing, not a job for the faint-hearted though as this involves opening the box and readjusting the clearance on the differential bearings.
 

·
Registered
Joined
·
3,932 Posts
Discussion Starter · #3 ·
Thanks for the response ,

My box is fine , but I am looking at a V6 that is what I would call a parts car , just trying to establish what potential value there is in the car for me .

I will strike gearbox from the list ;ol; Cheers and thanks
 

·
Registered
Joined
·
409 Posts
In short, Yes, its compatible.

Change the bellhousing and axles. THe only major internal difference between the saab autoboxes are the torque converters. thats it. 3.0 torque converters gives more high end torque to 2.3turbos and vice versa,,2.3 gives more low end torque to v6.
2.0 torque converter to 2.3 is more meant for city driving, not thatgreat on highways but it pulls alot better. (highway revs went from 1800 at 100KMH to 2400 at 100KMH)
Also, turbo boxes have a small vacuum hose going into the box, NA doesnt.
 

·
Registered
Joined
·
253 Posts
THe only major internal difference between the saab autoboxes are the torque converters. thats it. 3.0 torque converters gives more high end torque to 2.3turbos and vice versa,,2.3 gives more low end torque to v6.
I have to disagree here, there are a lot more internal differences than the tc only. Oil pump and back assembly, one way clutch, drums, axles, clutch plates, planetary gear set, valve body, just to mention a few. You'll be amazed how little parts are actually exchangeable between a V6 box and a 4cyl one.

2.0 torque converter to 2.3 is more meant for city driving, not thatgreat on highways but it pulls alot better. (highway revs went from 1800 at 100KMH to 2400 at 100KMH)
All torque converters used in 4 cylinder 9000's are identical, only the V6 has a different one. Also, at 100 kmh the box is in 4th and in 4th the TC is bypassed completely. So the differences in revs are not caused by differences in the TC but by different gear ratios. Now there are only two possibilities in gear ratio within the 4hp18: all planetary gear sets have the same ratio's, all boxes share the same final drive (77/18 = 4.28) so the only place to set the final ratio is in the intermediate gear set. Those are available in 56/55 (0.98) and 59/53 (0.90) only. Ignoring small differences in MY's and foreign markets, the general rule is N/a 4 cyl boxes have the 0.98 while the V6 ad turbo boxes have the longer 0.90. Still the difference is not that large, n/a's will do around 2700 rpm and T's will do near 2500 rpm at 100kmh.


Also, turbo boxes have a small vacuum hose going into the box, NA doesnt.
which is needed to adjust the 3-4-3 shift pressure to the increased low-rev torque of the turbo engines. A n/a box on a turbo will slip during shifting at higher loads.

Bottom line: stick with the box that came with your car if you want to be sure that it will work the way it should. Different versions of the 4hp18 have different numbers stamped on them for a good reason ;)
 
1 - 5 of 5 Posts
Top