88 doug nash conversion question
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
88 doug nash conversion question
I posted previously with problems related to the Doug Nash 4+3 and rather than pay 5 Speed.com $1250 for a professional upgraded rebuild I figured someone here has swapped out this unit for another 5 or 6 speed trans.
Anyone know what Trans. will be a capable easy swap?
Anyone know what Trans. will be a capable easy swap?
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
A ZF6 will fit and there are a number of members that have done that swap. But don't expect it to be cheap. It will be cheaper than a new TKO500 swap, but still will cost some.
Do a search using tags like "ZF6 swap". That should bring up some results that may even have step-by-step instructions.
Do a search using tags like "ZF6 swap". That should bring up some results that may even have step-by-step instructions.
Burning Brakes
Joined: Jun 2005
Posts: 1,188
Likes: 13
From: Wallingford Vermont
Unfortunately that $1250 for a rebuilt DNE overdrive is probably the cheapest option, but if you're "handy" and bargain shop you can swap for as much as (maybe a little less) than the rebuilt OD.
Search for ZF6 swap, T56, or T5 swap; lots of threads. ZF is nice, bulletproof (OE) swap but can be expensive especially of the ZF needs to be rebuilt.
T5 can be done but are somewhat "light duty" unless modified. Availability of GM World Class type T5 can be spotty. Plan on a rebuild but it's a fraction of the ZF rebuild.
T56 are slightly more involved with installation mods and slightly higher costs. They are strong and can be made stronger with a lot of aftermarket support.
I went with the T56 after I stumbled on a deal I couldn't pass up. Do your research. Assess your ability and resources and have at.
Search for ZF6 swap, T56, or T5 swap; lots of threads. ZF is nice, bulletproof (OE) swap but can be expensive especially of the ZF needs to be rebuilt.
T5 can be done but are somewhat "light duty" unless modified. Availability of GM World Class type T5 can be spotty. Plan on a rebuild but it's a fraction of the ZF rebuild.
T56 are slightly more involved with installation mods and slightly higher costs. They are strong and can be made stronger with a lot of aftermarket support.
I went with the T56 after I stumbled on a deal I couldn't pass up. Do your research. Assess your ability and resources and have at.
Race Director
Joined: Jan 2007
Posts: 14,919
Likes: 3,333
From: NYC NY
To keep the price down on an alternative you really have to be committed to doing a lot of legwork (shopping and labor) yourself as well as not being pressed for time.
Tech Contributor
Joined: Jun 2004
Posts: 20,847
Likes: 959
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I pulled the 4+3 out (of my '84) several years ago when it took a powder. I swapped in the Richmond 6 speed. Went in pretty smoothly (although it did require cutting the tunnel slightly for the shifter clearance). It's a nice shifting box (with the Long brand shifter).
Richmond had had some business difficulties a few years ago, and I don't know what their current situation is.
Richmond had had some business difficulties a few years ago, and I don't know what their current situation is.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
4+3 trans swap
A ZF6 will fit and there are a number of members that have done that swap. But don't expect it to be cheap. It will be cheaper than a new TKO500 swap, but still will cost some.
Do a search using tags like "ZF6 swap". That should bring up some results that may even have step-by-step instructions.
Do a search using tags like "ZF6 swap". That should bring up some results that may even have step-by-step instructions.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
4+3 trans swap
Unfortunately that $1250 for a rebuilt DNE overdrive is probably the cheapest option, but if you're "handy" and bargain shop you can swap for as much as (maybe a little less) than the rebuilt OD.
Search for ZF6 swap, T56, or T5 swap; lots of threads. ZF is nice, bulletproof (OE) swap but can be expensive especially of the ZF needs to be rebuilt.
T5 can be done but are somewhat "light duty" unless modified. Availability of GM World Class type T5 can be spotty. Plan on a rebuild but it's a fraction of the ZF rebuild.
T56 are slightly more involved with installation mods and slightly higher costs. They are strong and can be made stronger with a lot of aftermarket support.
I went with the T56 after I stumbled on a deal I couldn't pass up. Do your research. Assess your ability and resources and have at.
Search for ZF6 swap, T56, or T5 swap; lots of threads. ZF is nice, bulletproof (OE) swap but can be expensive especially of the ZF needs to be rebuilt.
T5 can be done but are somewhat "light duty" unless modified. Availability of GM World Class type T5 can be spotty. Plan on a rebuild but it's a fraction of the ZF rebuild.
T56 are slightly more involved with installation mods and slightly higher costs. They are strong and can be made stronger with a lot of aftermarket support.
I went with the T56 after I stumbled on a deal I couldn't pass up. Do your research. Assess your ability and resources and have at.
T-56 seems very large? I don't guess I would be able to reuse my stock console which is what I would like to do.
Would this bolt right up to the stock bell housing? would I need a different drive shaft?
Thanks
I saw Hurst has a complete TKO 600 swap kit but I'm waiting for the ball buster price.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
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Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
4+3 trans swap
I pulled the 4+3 out (of my '84) several years ago when it took a powder. I swapped in the Richmond 6 speed. Went in pretty smoothly (although it did require cutting the tunnel slightly for the shifter clearance). It's a nice shifting box (with the Long brand shifter).
Richmond had had some business difficulties a few years ago, and I don't know what their current situation is.
Richmond had had some business difficulties a few years ago, and I don't know what their current situation is.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Did I just screw up guys?
With only 80K miles, out of running car with no problems.
I made offer of $1500 including driveline and yoke , they accepted my offer !
Did I just screw up ???
Burning Brakes
Joined: Jun 2005
Posts: 1,188
Likes: 13
From: Wallingford Vermont
After receiving the answers from you experts I went to ebay and saw a 95 LT-1 engine and 6 speed trans complete with computer, harness all for $1695
With only 80K miles, out of running car with no problems.
I made offer of $1500 including driveline and yoke , they accepted my offer !
Did I just screw up ???
With only 80K miles, out of running car with no problems.
I made offer of $1500 including driveline and yoke , they accepted my offer !
Did I just screw up ???
No I wouldn't say you screwed up providing shipping doesn't bite you and hopefully the selling wasn't hiding anything. A good running T56 with bellhousing is in the $1000 - $1300 range. Your console remains although it will be modified a little. There are a bunch a threads on here about doing the T56. So a few of us have broken a trail for ya. I'd recommend reading them all but here's a couple to get you started.
https://www.corvetteforum.com/forums...acement-2.html
https://www.corvetteforum.com/forums...arts-list.html
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
4+3 trans swap
No I wouldn't say you screwed up providing shipping doesn't bite you and hopefully the selling wasn't hiding anything. A good running T56 with bellhousing is in the $1000 - $1300 range. Your console remains although it will be modified a little. There are a bunch a threads on here about doing the T56. So a few of us have broken a trail for ya. I'd recommend reading them all but here's a couple to get you started.
https://www.corvetteforum.com/forums...acement-2.html
https://www.corvetteforum.com/forums...arts-list.html
https://www.corvetteforum.com/forums...acement-2.html
https://www.corvetteforum.com/forums...arts-list.html
Seller said they drove it shifted fine in all gears and engine runs great.
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 603
From: Minneapolis Mn
my 86 convertible came with the DN 4+3. Some time around 10 yrs ago (best guess based on s/n on it) the tranny was changed out for a Tremec TR3550 5 speed. I have been under the car and cannot find any hacks done down there. The only mod I did find was a DakotaDigital unit to change the signal out of the tranny so it works with the original dash.
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
my 86 convertible came with the DN 4+3. Some time around 10 yrs ago (best guess based on s/n on it) the tranny was changed out for a Tremec TR3550 5 speed. I have been under the car and cannot find any hacks done down there. The only mod I did find was a DakotaDigital unit to change the signal out of the tranny so it works with the original dash.
Got off ebay from a wrecking yard in Texas for $1500 .
I amm currently looking at shipping options.
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 603
From: Minneapolis Mn
Thanks, I don't know if you noticed my other post about buying a complete LT-1 engine and ZF6 trans with all goodies . Came out of a 95 with only 80K miles on it so I'm hopping for a semi-easy swap?
Got off ebay from a wrecking yard in Texas for $1500 .
I amm currently looking at shipping options.
Got off ebay from a wrecking yard in Texas for $1500 .
I amm currently looking at shipping options.
If you got what you want, more power to you. Hopefully you got everything you need for the conversion.
Burning Brakes
Joined: Jun 2005
Posts: 1,188
Likes: 13
From: Wallingford Vermont
You said six speed so I ***-umed it was a T56. A complete LT1/ZF should be a great swap. I know they're some ZF swap threads that will give you all the info. The LT1 swap might be a little more involved, but I would imagine someone has done it before. Have at it! 
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
LT1 swap from a 4+3
Hey thanks I will do that
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
Since '88(?) and up cars came with the ZF, I would think you could source a six speed console so you wouldnt have to mod anything but the trans tunnel maybe.
Good find and price on the LT1/ZF combo. Hope everything is ok with it and you get it to you in a reasonable time and cost.
Good luck!
Good find and price on the LT1/ZF combo. Hope everything is ok with it and you get it to you in a reasonable time and cost.
Good luck!
Thread Starter
Instructor
Joined: Jan 2015
Posts: 203
Likes: 2
From: Port Costa CA
Yes thanks, by the way for future reference about shipping I used YRC freight or Yellow from Waco, Tx to California $168 . Of course the seller has a forklift so that saved some plus they ship to a distribution point in Ca where I have to pickup and they will put into the back of my Pickup truck.