This is the stock 5spd transmission that bolted up to the 2.0L 8V turbo (C20GET ) in the turbo Sunbirds and turbo Grand Am cars.
It was also used very heavily in the GM V6 applications and is known to be a fairly solid gearbox.
here is some info.... http://www.rodneydickman.com/getraginfo.htm
Here is what someone had to say on another forum......
OK, you're all in the right ballpark as far as information goes, and most of what has been posted thus far is correct for the most part.
The HM-282 was introduced to replace the 4-speed Muncie in V6 equipped Fieros - true. It was also used in various other platforms as early as 87, if not before, such as the A-bodies (Celebrity, 6000), J-bodies (Cav, Sunbird), and W-bodies (GP, Grand Am, Cutlass, etc). There may have been one or two other platforms, but I'm going by memory at the moment, so you'll have to excuse me.
The transaxle was referred to as the Muncie/Getrag HM-282 5-speed (5TM40 was the "official" designation, 5-speed, transverse mount, 40 class torque handling). It was used in applications when engines with more power were installed, such as the V6 cars, the Quad4, and the 2.2L turbo found in some Sunbird GTs of the late 80s. Until 1989, the transaxle had an external clutch release arm. Starting in 1990 (I know this for sure, as I've got a 1990 Cav in my garage right now that I'm ripping apart) the slave cylinder bolts right onto the back of the bellhousing. I am not familiar with changes beyond this year and when they were implemented.
The information previously posted about the platforms that used the HM-284 was, as far as I can tell, correct. It did indeed have a very limited production run, and was implemented in a very limited number of platforms.
Now for torque handling capacity: belive it or not, the HM-284 is not worlds above the HM-282. According to the following link (not the one I was originally looking for, but you can Google it to find substantiating information) the HM-282 is capable of 200-275lb/ft, while the HM-284 is capable of 250-300lb/ft. (http://www.statikdesign.com/scratchbuil ... on_v21.PDF)
As some of you already know, I'm in the process of installing a 3.4RWD with GenII aluminum top end into my '90 Celebrity. I've chosen the HM-282 for my manual transaxle. Why would I make a "silly" move like this? Several reasons:
- The HM-282 is as common as skunk stink - it can be found in a plethora of Z24s in the boneyard, and can usually be had for around $200-$300. I just purchased a BRAND NEW unit meant for a '92-'94 GrandAm with a Quad4 which I will be swapping the bellhousing on to put behind the 3.4. I got it on eBay for $120US! The same seller has more for sale, but he's asking like $149 for them I think. Just do a search for grand am transmission, you'll see it if the auction is still going.
- There are aftermarket parts available for the HM-282 transaxle which I have yet to see for the HM-284, such as different gear sets and final drive gears, not to mention limited slip differentials with several designs to choose from. Like I said, I have yet to see any such parts for the 284.
- Cost for the HM-284 from a boneyard: I've never found one yet in the past 7 years.
- Cost for rebuild parts for a 284: last I checked, they don't exist. Apparently you are only able to send the transaxle, in it's entirety, to the manufacturer (would this be Getrag? I don't even know where you'd have to send it) and pay $2500 to get it rebuilt. If this has changed, please let me know.
All in all, I chose the Muncie/Getrag HM-282 5TM40 because, even if I do eventually grenade it, I can get a replacement as cheap as $200 and I'm up and going. And on top of that, I fully plan on installing an LSD into it.
Just so you know, I also plan on putting this transaxle behind a Cadillac Northstar motor sometime in the not-too-distant future. There's even a gentleman that's already in the midst of doing so in a Beretta. Check it out: http://www.cadillacforums.com/forums/ar ... php/t-4058
As for the question about why Rodney Dickman's website doesn't cover the transaxles of '89 and later - it's because his site is a Fiero site. Fiero owners aren't usually concerned with much stuff beyond '88. In '89 GM started outfitting these transaxles with electronic VSS units as opposed to cable driven (very few, of the transaxles, including the one that's in the '90 Cavalier I bought, had a combination sending unit which had BOTH cable and electronic VSS sending capabilities). It's a big hassle for a Fiero guy to covert an electronic VSS back to a cable driven unit, so they just go with a pre-'89 transaxle most times.
