After searching the forum, it sounds like swapping a manual transmission into my '85 IROC isn't a great idea, unless I want to get a built one for $$$ (I guess a 4th gen 6 speed might be an option).

So now I'm not sure what way to go. The previous owner swapped in a 5-speed automatic but I have no idea what it is out of or what trans it is. And since it has a B & M Slap Shifter (that I hate), I'm not sure if I can just put the stock shifter back in, if I should get this trans rebuilt or buy a normal 4-speed and put that in instead.

I think my plan right now is to take off the slap shifter and install a normal shifter (if the stock one will work) and then do...something with the trans when I do the engine over the winter. Advice?

 

I have a tough time believing that is a 5sp auto. I'm not aware of any that would be a direct swap. If it is indeed a 5sp; it would have to have been quite the fabrication work....and even then expensive. It still sounds to me like is the 4l60. Take a picture of the pan, I can ID from that. Then if it is a 4L60, put a stock shifter on it and call it good. The T56 swap will cost a fair bit of money to pull off as well. If shifting is that important to you, then go for it.

 

I don't know of any easily swapped 5 speed automatics. Yep, I'm also curious to see what 5 speed he has.
But how about a 6 speed automatic instead, those are on the market. I wouldn't mind having one, "Dear Santa"....TCI® Transmission Packages - TCI® Auto
And it's only (wheeze) 6 grand for the whole package! TCI Auto 271600P - TCI 6x 6-Speed GM 4L80E Automatic Transmission Packages - Overview - SummitRacing.com
‪TCI hits on their 6 speed automatic transmission at PRI 2008‬‏ - YouTube

 

Okay, will do - I'll snap a picture tomorrow and post. Thanks for the help, and any additional advice is appreciated.

 

I managed to get a picture of the trans tonight. Not great quality, it was with my cell phone. See attached.

While I had it on the lift, I noticed that the trans has a Jasper tag and Production #. Apparently, it's an aftermarket trans. I emailed the number to Jasper, I'm hoping they can get me some information on that. Not sure if looking at this picture will do any good or not.

 

I dunno man, I'm seeing a 700R4 pan here. This link shows the different pan configurations: Chevrolet Chevy Transmission Identification and Decoding
I don't know what you're "feeling" to think it's a five speed?

 

i think 5th speed is the converter locking in 3rd, 700r4/4l60 would bolt into a 3rd gen fairly easily

 

Would somebody really go to the trouble of riveting a Jasper tag onto the bell housing if it's really just a stock trans that they want someone to believe is something else?

As for why I think it's a five speed...I guess I don't. Bought the car after driving it about 3 miles on city streets, drove it home and then parked it and started working on it. When driving home, I thought that it had 5 gears but really, it might only have four. The previous owner told me it was a 5-speed that they put in it, not sure why he would lie.

In any event, I'm just trying to figure out what it is & what I should do. Plan on putting a 383 in the car over the winter, not sure if I can (or should) just leave this trans in it, get something better, get it rebuilt, etc.

 

That is indeed a 700R4. Either the person who sold it, didn't know themselves, or they just flat out lied. Put the stock shifter back in it, and enjoy what you've got. As far as the resto/motor upgrade; make a plan first then completely price everything out. So many guys buy these cars with great plans but don't factor all the cost in, and end up selling at a huge loss.

 

What is that "something else" that the tag says that makes somebody believe it is? Jasper puts their tag on things they rebuild, that's all. Does the tag say it's a five speed?
And as far as the torque converter locking up feeling like a fifth gear...I've had a number of cars with the 700R4/4L60, and when it locks up, I can see a drop of maybe 200 rpm's on the tach, and a slight slight glide into lockup. If you know what a gear shift feels like, you'll know lockup feels nothing at all like that. And if I had my eyes closed so I can't see the tach, the difference would hardly be noticeable. I hope you didn't pay extra for the car since it had a "five speed automatic".