overdrive bad need advice
Thread Starter
6th Gear
Joined: Mar 2011
Posts: 6
Likes: 0
overdrive bad need advice
I have a 1985 corvette coupe 4 speed with overdrive unit. the overdrive went bad. Saw company named Motor City Speed Works has a rebuilt unit. Has anybody bought one of these or know someone who has. Was it ok work well. I know a 5 speed is option to install but my thinking is switching the overdrives would be easier and cost less. I will have a shop that has done work on it before do the job. thought posting here is best way to get good advice as lot of people on that know lot about corvettes. Thank You.
Drifting
Joined: Feb 2006
Posts: 1,423
Likes: 96
From: Magnolia Tx
I'm not familiar with that shop but the O.D. unit is a pretty simple 2-speed automatic. A reputable shop with the parts shouldn't have too much trouble with it. I converted mine to a T56 from a '95 Z28. I'm very happy with it, but.... if i added up all the receipts and counted the hours of modding headers, hydraulics, speedo adapter wiring, tunnel mods, etc. I'm sure that rebuilding the O.D. unit is way more cost effective.
Safety Car
Joined: Aug 2013
Posts: 4,430
Likes: 608
From: Minneapolis Mn
Happens my 86 originally came with the 4+3 and prior to my purchasing it the tranny was change to a Tremec TR3550 5 speed. Far as I can tell the only mod to the car was putting in a Dakota Digital signal converter to retain the original Atari speedometer due to the differences in signal generation. All the gauges work as they should and it has a Hurst shifter on it so it looks appropriate to the car.
Personally I'd prefer a little closer gears in it but this is a pure cruiser so it's something I can live with.
It works, that's all that matters to me. Good luck on your project.
Personally I'd prefer a little closer gears in it but this is a pure cruiser so it's something I can live with.
It works, that's all that matters to me. Good luck on your project.
Burning Brakes
Joined: Jun 2005
Posts: 1,191
Likes: 15
From: Wallingford Vermont
I'm gonna have to disagree with Benny. I know it's not rocket science and the DNE 4+3 has many of the same parts as automatic, BUT here's were things start getting tricky: Some (many?) of the parts are No Longer Available. I know personally, the "adapter plate" that carries the front bearing is NLA and setting up the lash on that bearing is CRUCIAL to OD life.
MOST transmission shops are not familiar with this OD and have no experience with it. (Nor special tool or technical info). Is that who you want putting your OD back together?
The only shop I know of that did have experience with them is SK Speed out of NY. http://skspeed.com/ (I think my OD was done by someone that I believe was associated with them before SK Speed). This OD does have a bad reputation, but they're fun to drive when they're working correctly.
MOST transmission shops are not familiar with this OD and have no experience with it. (Nor special tool or technical info). Is that who you want putting your OD back together?
The only shop I know of that did have experience with them is SK Speed out of NY. http://skspeed.com/ (I think my OD was done by someone that I believe was associated with them before SK Speed). This OD does have a bad reputation, but they're fun to drive when they're working correctly.
Last edited by DanZ51; Jun 2, 2016 at 01:25 AM.
Drifting
Joined: Feb 2006
Posts: 1,423
Likes: 96
From: Magnolia Tx
I really liked mine before it died, the T-10 half is still fine in it. I have about $3000 in my conversion (don't tell my wife) and you cant tell by looking that the car didn't come from Bowling Green this way. That doesn't count my labor, lots and lots of labor. The DNE O.D.
costs that much to fix? My dead core probably has some value then.
costs that much to fix? My dead core probably has some value then.
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Racer
Joined: Jul 2015
Posts: 313
Likes: 15
From: Modesto Ca
I have 2 complete 4+3 units that are getting pulled from cars but I almost hate to sell them.Why?I dont mind helping fellow members out but if I sell something and it fails soon it wasnt worth selling in the first place.The 1987 car I have is getting a ls drivtrain and the 85 car is donating its rear suspension into a 1957 210.The 1987 will be on the road for a few weeks until its day at the rock crawler shop and I intend to check the od unit before its removed.I am going to direct wire it.I will know for sure if it works.