Question about Seville STS tranny

[brandon6976]

Hey guys I'm new to the forum. I don't actually own a caddy or real luxury car however a close friend of mine who isn't very computer savy does. He was wondering.

He has a 96 STS with the 4.6L northstar engine. Someone was telling him its possible to put a manual gearbox in the car. Is that true ?? do you guys know what tranny would fit on the car ?? Any help or tips would be greatly appreciated.

:dj:

 

[Roy]

Major Custom work needed

With out doing my home work, first find a custom gear box for a north star, I have never seen a manual in an STS but I have seen a North* in a custom hot rod 34 chevy with a 5 speed trany, but it was also converted to RWD,

Beware the price tag on the custom Hot rod was around 75K US with that money anything is possible, unless your frenid is a really well equiped machanic and fabricator, don't try this a home.

 

[brandon6976]

With out doing my home work, first find a custom gear box for a north star, I have never seen a manual in an STS but I have seen a North* in a custom hot rod 34 chevy with a 5 speed trany, but it was also converted to RWD,

Beware the price tag on the custom Hot rod was around 75K US with that money anything is possible, unless your frenid is a really well equiped machanic and fabricator, don't try this a home.

I'm not to worried .. you joke but my friend is a mechanic who owns his own shop and fabs up stuff all the time. However He was wondering if anyone knew of a manual gear box that was FWD that actually fit onto the northstar.

So like does the tranny say from the G6 of one of GM's other FWD manual gearbox cars

 

[Jibit]

How do they do the conversion on the Fiero's? The northstars that are put in those are probably different but it wouldn't hurt to take a look at those first.

 

[brandon6976]

good point !! I know a friend who used to owns one. I'll check out the fiero forums as well. Thanks for the tip. If anyone else has any good idea's or just knows if its been done please speak up !!!

 

[danbuc]

It would be easier to by a different car with a manual tranny already and swap the motor for a northstar. Putting a manual transmission in an STS would probably be as hard as converting it to rear wheel drive. The 4T80E transmission is computer controlled. If you were to swap it out for a manual, you would have to install a clutch pedal and linkage, find a way to make it work with the computer (or bypass it so the car will still run) and find a FWD Transmission that is good for 300hp and 295 ft lb of torque. Even the traditional rear wheel drive transmissions like the 700R4 have to be modified slighty to bolt up with the northstar. You would also have to swap out the flex plate for a flywheel if your switching to a manual. In response to the Fiero, I don't know what transmission they use for that (they probably just keep the 4T80E) but there are no "different" kind of northstars other than those that get placed into Cadillacs. There are only two current versions of the front wheel drive northstar engine. The Vin# 9 engine (STS 300hp, 295 ft lb of torque) and the Vin# Y engine (275hp, 300 ft lb torque). The easiest way to get a manual transmission caddy would be to trade the STS in for a CTS (preferably the CTS-V). Good Luck.

 

[speedyguy]

RWD is somewhat pointless with the fwd caddy. There are options for the 4L80-e that modify it in a way to make it more of a standard. The same might be available for the 4t80-e but the cost would be unreal. I have seen a caddy with a northstar in the front and rear for a 600hp caddy. lol

I am personally working on a rwd ls1 Pontiac Bonneville. More for fun not practical
.

The 4t80-e can take quite a bit of hp though (over 500hp) and really can be made to shift more like a stick with a performance build. Your buddy needs to look up rebuilt 4t80-e transaxles.

The only way he could make it like a stick is with steering wheel controls. There are "mooneyeyes" products that you can get that take the tranny closer to a stick.. you will also be wise to adapt grand prix steering wheel paddles.

The obd2 caddy computer can be disassembled but the cost was the issue and lack of demand makes it a 5000/00 deal..or you can get a piggy back kit installed for around 2000.00. If there is group interest the stock computer can be done cheaper.

The easiest is to move over to the obd1 northstar chip computer that can be modified and can be made to work with your newer n*.

Get this http://www.mooneyes.com/support2/smartshift.html
Then get specialty tranny guys like bulletproof (Found them advertised through a shop on froogle) and wala your set. I almost did a fwd northstar Bonneville but figured it would just be another caddy in Pontiac skin. Lol then even worse gm did it.

The Bonneville with an ls1 will probably happen too but I hope to be done before gm makes one.

I guess I’m saying it can be done but make sure your doing for the right reason because it becomes a project of interest not practicality. While you’re at it you might as well turbo it.