Kemmotorworks

As I'm searching I'm asking as well because I don't have much time. I have a chance to buy a 78' cheap and will the transaxle and 5 speed swap into my 84'? Is there alot of difference between the 4.5 and 4.7 in means of bolt locations or any thing else? I have 2 days most to decode if I want the donor car so I'll be checking in as I'm hunting my answers down. Thanks

James Bailey

With a complete donor car you will have everything you need.....but it involves a LOT of parts. Also the odds are the 78 trans will NOT shift into second gear very well once you get it installed due to wear of the syncros, shift sleeve etc. So unless you can drive the donor car you may just be buying core parts for a rebuild.

Rob Edwards

Had meant to respond to this but I don't know the early cars well at all- won't there be a problem trying to install the (different length) '78 5-speed torque tube in the '84, or he can just transplant the whole '78 bellhousing/TT/trans/rear crossmember in the '84?

Was the 5-speed TT always the 6-bolt pattern at the rear, or is that just 80+?

James Bailey

right going to need to gut it from crank back.....transfer everything form the donor including rear suspension cross member. Then fabricate the mounting for the clutch master cylinder use the smaller brake booster or update the clutch master either way the booster brake master has to come off
Like I said LOTS of parts and if early 78 the short clutch shaft is the odd ball length short one N L A if worn out . It really is a pretty big job putting in a bunch of possibly 37 year old used parts.

chrisjbell

It can be done but do make sure you get the whole donor car. I am taking a complete driveline from a '79 and putting it in my '80 (the subframe on the '79 was bent).

The section of the firewall with the clutch master cylinder mount from the '79 had different looking sheetmetal than my '80 firewall. The piece I had was too small so YMMV but that was one of my challenges.

The brakes on my '80 are the older style so I don't lose anything by changing out the entire rear setup but you'll probably want to swap your brakes and hubs over to the manual transaxle and cross member.

James is right - its a LOT of work. For me it is a labor of love - I really enjoy doing this kind of thing. If you aren't planning on doing the work yourself I'd strongly recommend selling your automatic and buying a manual. If you like mechanical challenges, you've got the right project.

It is quite do-able, though.

Vilhuer

Gearbox to TT mounting is always same six bolts. TT center shaft to transmission input shaft is the problem between G28/03 and later boxes. Which is obviously not a problem in this case when parts come from same donor.

tlister67

My 78 has 6 bolts TT to tranny.

Kemmotorworks

Thanks guys. There's not alot of info out there on this. after lot of homework and digging, without being able to drive the car I'm scared about the 2nd gear. Sure would suck to go through all that work to end up with a a box that doesn't like to shift. I originally had to tomorrow, Friday buy guy changed his mind on scraping it and it's gonna be around for another month. If sticks were readily avalible I wouldn't be thinking of a swap but hard to find one that's not an auto anymore.