Cadillac Owners Forum banner
14K views 35 replies 19 participants last post by  Fiero STS 
#1 ·
Hello all,
I have a rather strange question on a kind of "not worth it" car. I have a buddy who recently blew the auto (4T80E) transmission out of his Oldsmobile Aurora. Since this car is one heck of a beast (not like my Concours, of course), he is interested in putting a manual transmission in the aurora. I know that the engines in these Olds cars have the exact same tranny bolt pattern as it's bigger caddy brothers and sisters, so I was wondering - Has anyone ever seen a North* powered FWD caddy or aurora with a manual transmission......or even better yet, is it possible? If this was rear-wheel drive, It would be a snap.....but of course it isn't that perfect of a situation. Thanks for any help, as it is always appreciated.

Later!
Jason
 
#2 ·
I dont think its possible....... There arent any (to my limited knowledge of GM tranny) FWD trannys that will bolt on...... Everything would have to be custom......

Come to think of it, did GM make a FWD MT in that era...... Off the cuff, I cant think of any, all are automatic.........
 
#3 ·
96concours96

I entertained the idea myself, and gave up due to the time and expense of such an difficult task. Has it been done? Not to my knowledge for FWD cars. Could it be done? Yes I think it could, but might be very diffucult and expensive. Keep us posted on any progress if he pursues this project.
 
#4 ·
No, as far as I know.

I was looking into buying a 1994 Eldy with a blown engine and slipping transmission to convert to a front drive stickshift northstar. It was kind of a dream of mine, I love to take a car and do something wild with it. Well, they told me it was impossible, and so far I agree. I havent found anything to prove its possible. I just gave up and let the car go. The only way to do so would be to convert the car to rear wheel and put the engine in like a conventional RWD, but that is just plain ridiculous. I would give it up. Buy dont fret, my next project is a 1984 Supra Celica (remember those?) with an engine out of a mid 80's T-Type. I found a motor, but its in bad shape. Wish me luck. (sorry to get off topic)
 
#5 ·
Its a machine...... unlike the human body, you can build anything you want....... If he really wants to, he could drop 20k for a completely custom manual tranny......
 
#6 ·
I agree....... It would be FAR easier (and cost effective, although stuff like this isnt cost effective at all) to convert it to RWD and use a RWD tranny.......

Hmmmmmm...... Maybe we could put together a kit to convert FWD northstar caddies into RWD........

If thats possible...... Ta-ta Q45.... hello RWD STS!!! :burn:
 
#7 ·
96concours96 said:
Hello all,
I have a rather strange question on a kind of "not worth it" car. I have a buddy who recently blew the auto (4T80E) transmission out of his Oldsmobile Aurora. Since this car is one heck of a beast (not like my Concours, of course), he is interested in putting a manual transmission in the aurora. I know that the engines in these Olds cars have the exact same tranny bolt pattern as it's bigger caddy brothers and sisters, so I was wondering - Has anyone ever seen a North* powered FWD caddy or aurora with a manual transmission......or even better yet, is it possible? If this was rear-wheel drive, It would be a snap.....but of course it isn't that perfect of a situation. Thanks for any help, as it is always appreciated.

Later!
Jason
Does the Northstar share a bellhousing bolt pattern with any other engines?
 
#8 ·
I think there is...... I couldnt tell you which one.......

It would probably harder to find a rear end and mount the driveshaft.......
 
#9 ·
*UPDATE*
Since I posted this awhile ago, I have found many dead ends, and many possiblities.

For one, the Oldsmobile Aurora in later years had two engines: The 4.0 liter (basically a NorthStar v8 - same bolt patterns as the Cadillac brother), and a smaller v6. The interesting part is that this v6 is also shared with the Olds Alero-WHICH could come with an optional 5 speed manual! I don't know if olds used the same bolt pattern for the v6, I do know, however that the exact same auto (the 4T80E) was used on BOTH the v8 and v6 versions of the Aurora. Assuming that GM was lazy as usual, I would guess that an Alero manual tranny would just simply snap in. Anyone have any input on this?

Second option: A friend of mine has an article out of a magazine that says certain FWD oldmobiles from the eighties have the exact same bolt patterns and constant velocity joint lengths as it's newer olds brothers. However, it also says some of the older oldmobiles also share the bolt pattern with, you got it, the NorthStar! This is going to take ALOT of research, but this article made it sound like someone had already done this conversion to a late nineties Eldorado.

Third and hardest: Amazingly, this is kinda funny. If we were to convert it to RWD, then I found something very interesting that would make it extremely easy to do so. Just use a transmission and rear end out of an Isuzu Trooper or Amigo. That's right-the tranny bolts right onto the NorthStar engines! Obviously, the Conversion part would kinda stink, but I thought it was interesting that our engines would just simply bolt right up to an Isuzu tranny. I know they're GM, but that's kinda funny. So if any of you guys have a totaled NorthStar car, and an Isuzu, HAVE AT IT!

Anyway, sorry I couldn't give more info. I'm gonna track down the writer of that article mentioned in #2, and check out the validity of this claim. As always, if anyone has further input, I greatly appreciate it!
Later!
 
#10 ·
I think you are on the right track and I bet that it is possible to put together a manual shift Eldo or Aurora from mostly junkyard parts. The good news about the older parts bolting up is that the older parts are frequently cheaper.

20 years ago I used to combine all sorts of engine and transmission combinations into different vehicles. It was amazing what would bolt together. Some combinations worked great, and some were not so great. Back then I could tell you about all the different bolt patterns, but now I don't know any of the current patterns.

While you are fishing around, maybe you could find a combination for a Manual Shift, All-Wheel Drive NS Aurora. I bet that is completely possible also. The drawback is going to be longevity. The NS has more torque and power than most of the V-6 engines and the Aurora is heavier than most of those older Oldsmobiles.

GM ownes part of Isuzu so it is not surprising that over time parts are going to become more interchangeable. I think I read recently that GM purchased some or all of Isuzu for the Diesel technology and has shared some of that technology with Honda in exchange for the Variable Valve Timing technology that is being inplimented on the new Northstars.

Good luck with your project, however it turns out.
 
#11 ·
The V6 bellhousings out of the 90's S-10's/Sonoma/S15 and F-body (V6 Camaro/Firebird) will fit the northstar with a bolt hole moved (only one), a pocket welded in for the starter and the lower starter location welded shut (wouldn't exactly want sand getting in your clutch now would you?). Firebird/Camaro bellhousings are the stronger of the two, and unlike (or at least I assume so) the Isuzu bellhousings, these will bolt to older, beefier transmissions from GM (like the Muncie M-22 "Rockcrusher", various Saginaw, T-10 and T56 transmissions).
 
#12 ·
96concours96 said:
*UPDATE*
Since I posted this awhile ago, I have found many dead ends, and many possiblities.

Olds Alero-WHICH could come with an optional 5 speed manual! I don't know if olds used the same bolt pattern for the v6, I do know, however that the exact same auto (the 4T80E) was used on BOTH the v8 and v6 versions of the Aurora.

(SNIP)

Third and hardest: Amazingly, this is kinda funny. If we were to convert it to RWD, then I found something very interesting that would make it extremely easy to do so. Just use a transmission and rear end out of an Isuzu Trooper or Amigo. That's right-the tranny bolts right onto the NorthStar engines! Obviously, the Conversion part would kinda stink, but I thought it was interesting that our engines would just simply bolt right up to an Isuzu tranny. I know they're GM, but that's kinda funny. So if any of you guys have a totaled NorthStar car, and an Isuzu, HAVE AT IT!
Howdy

I found this thread as a part of a search to find the dimensions of the bellhousing bolt holes for GM 60 degree engines.

First from what I understand the Oldsmobile Alero mentioned above is a rear wheel drive. It shares the same transmission, except for gear ratios and tail shaft as the one in Isuzu SUVs, Trooper, Rodeo, and Amigo. It's the 4L30-E transmission. The engine in the Alero is supposed to be a 4.0L Aurora (Northstar) engine with the aft 2 cylinders lopped off. :)

Second. Where did you find the information about the Northstar/Isuzu swaps? I hope it wasn't my site, only because I am looking for more information than I have, so another source would be helpful.

Third The Northstar series engines do have the same bolt pattern as all the GM 60 degree engines. Except that there is one bolt hole that has to be relocated, and the Northstar series engines have the starter on the top of the engine between the cylinders.

Lastly, Does anyone have the dimensions of the bellhousing pattern from the Northstar series of engines? I need the information to footnote some of my data.

Thanks

Bruce

http://myweb.cableone.net/bcanderson/
 
#15 ·
Uhm, don't know who told you the Alero is RWD. They're not. Only 1 olds going still has RWD, and that's the Bravada SUV. While the Alero does have a 5 spd available, I thought it was only mated to the 4cyl version. If it is indeed on the V6, someone can correct me, I dont object. The other drawback, is the durability. The 4t80-e is a tank of a tranny. The Alero's tranny isn't so tough....
 
#17 ·
The "shortstar" 3.5V6 found in the Aurora is NOT the same V6 in the Alero. The Alero gets a 3.4 pushrod V6 that is basically just a stroked 3.1. Its the Intrigue that gets the shortstar and it is mated to a 4T60E in that car.

Also, The 5 speed Getrag that is optional in the Alero (and the grand am which is the Aleros twin) is ONLY available with the 4 cyl.

The only option I could possibly think of would be a rebuilt and beefed up 5 speed from an early 90s grand prix with the 3.4 DOHC V6. In stock form, they would not handle the torque though.

-Eli
 
#21 ·
notherstars have been mated to manual transmissions , go look up v8 archie of v8 fireo fame , the isuzu built 5 speed that was mated to the original 60 degree 2.8 in the fireo gt do sorta bolt up to the 60 degree n* problem being is the bell houseing on the isuzu/fiero 5 speed doent have the nesseary hole for the n*/aurora starter , other problem being is this works in the fireo , the loads on the tranny would be diffrent in another car , what works on a 2500 lb fireo wont work in a 4,000 lb aurora

the 4t80e is the only real solid tranny availbe for high output GM front wheel drive apps
 
#26 ·
Yes you can put a manual trans behind a N* the Fiero Getrag 5 speed bolts up with a little mod to the bellhousing for starter clearence and one bolt hole also there are some guys on the Pennock's Fiero Forum who have been working to get a flywheel made for the N*. Problem with a FWD trans is GM never put a manual trans behind anything with more than 250hp and 250lbs torque. so if you go this route be sure to have spares as the hp and torque will kill these transmissions. also the gear ratios are not optimal for N*'s
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top