TKO 600 Upgrade?
Thread Starter
Melting Slicks
Joined: Nov 2006
Posts: 3,396
Likes: 1,812
From: Apple Valley, MN
TKO 600 Upgrade?
I bought my TKO 600 about 12 years ago. Still in the box, waiting for a break in life to finally get it put into the car. Since more than a decade has passed, I’m wondering if there are any recommended modifications I might consider before I install it because once it’s in the car, I have no plans of ever removing it so if there ever was a time for opportunity, it is now.
To be clear, this car will be babied. Yes, I have 500+ HP/torque on tap but zero plans to abuse it so I’m not looking for changes that will allow me to, say, shift at 6000 RPM and the like but if there are sensible mods to generally improve my experience with it, I’d appreciate all inputs.
To be clear, this car will be babied. Yes, I have 500+ HP/torque on tap but zero plans to abuse it so I’m not looking for changes that will allow me to, say, shift at 6000 RPM and the like but if there are sensible mods to generally improve my experience with it, I’d appreciate all inputs.
Melting Slicks
Joined: Dec 2009
Posts: 3,229
Likes: 656
From: Thunder Bay
I installed my TKO 600 almost that long ago with no modifications and it works beautifully. The only mods I am aware of involve the synchros as the trans has a bit of a reputation for not shifting smoothly. I did find the trans was a little challenging to shift when it was new, but after a couple thousand miles it smoothed right out. I probably have about 10,000 miles on it now and its smooth as silk. The only complaint I have is it leaks like the proverbial sieve. I have always added a couple hundred cc's of oil every season to keep it topped up. Last year I decided to put some dye in it to see exactly where it was leaking. Long story short, everywhere.
Melting Slicks
Joined: Jul 2006
Posts: 2,286
Likes: 487
From: Salmon Arm, BC
I also put mine in many years ago, and it has worked flawlessly for me....totally transformed the car into a blast to drive compared to the 4 speed. I spent a lot of time driving on the highways back then so the overdrive was really welcomed.
As for modifications, If you drive it as you say you will, you'll have zero issues. I've had mine to the dragstrip, and was shifting at 6500 RPM and only missed that 2-3 shift once....then I figured out how to do it...no issues since.
I'm pretty sure you'll ask yourself why I waited so long to put it in....
As for modifications, If you drive it as you say you will, you'll have zero issues. I've had mine to the dragstrip, and was shifting at 6500 RPM and only missed that 2-3 shift once....then I figured out how to do it...no issues since.
I'm pretty sure you'll ask yourself why I waited so long to put it in....
Thread Starter
Melting Slicks
Joined: Nov 2006
Posts: 3,396
Likes: 1,812
From: Apple Valley, MN
@drwet Thanks. Leaking badly? That is very disappointing to hear. My dad rode Harleys for 50+ years and there always was a drip pan underneath it. I do NOT want to experience that. Maybe first order of business is to seal all the seams?
Melting Slicks
Joined: Dec 2009
Posts: 3,229
Likes: 656
From: Thunder Bay
@drwet Thanks. Leaking badly? That is very disappointing to hear. My dad rode Harleys for 50+ years and there always was a drip pan underneath it. I do NOT want to experience that. Maybe first order of business is to seal all the seams?
I use the same approach with my trans. Not sure what the solution is, but yes, virtually every seam and seal in the transmission is seeping lubricant. I figure one of these days I am going to have to pull the trans and have someone replace all the seals and gaskets. I am reluctant to attempt it myself, and I am even more reluctant to let someone else open it up. In the meantime I live with it. As to why it is happening, I'm not sure. There was a time when synthetic lubricants had a reputation for seeping past seals and gaskets. Perhaps there is some truth to that and I have one of the susceptible components. (I did have a 2001 KLR 650 that had that problem.) I do run Amsoil synthetic in my TKO 600.
Sorry I can't offer much help beyond relating my experience.
Melting Slicks
Joined: Oct 2001
Posts: 2,064
Likes: 1,382
From: Halifax, Nova Scotia, Canada
I installed my TKO-600 in 2006. No leaks at all, still shifts very smoothly. There is about 30+K miles on the transmission now.
I purchased from Keisler's. I remember some advertising from them at the time, that stated they took all the transmissions apart and reassembled, for some reason.
Maybe they're the ones that don't leak.
I purchased from Keisler's. I remember some advertising from them at the time, that stated they took all the transmissions apart and reassembled, for some reason.
Maybe they're the ones that don't leak.
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Thread Starter
Melting Slicks
Joined: Nov 2006
Posts: 3,396
Likes: 1,812
From: Apple Valley, MN
I installed my TKO-600 in 2006. No leaks at all, still shifts very smoothly. There is about 30+K miles on the transmission now.
I purchased from Keisler's. I remember some advertising from them at the time, that stated they took all the transmissions apart and reassembled, for some reason.
Maybe they're the ones that don't leak.
I purchased from Keisler's. I remember some advertising from them at the time, that stated they took all the transmissions apart and reassembled, for some reason.
Maybe they're the ones that don't leak.
Melting Slicks
Joined: Jul 2006
Posts: 2,286
Likes: 487
From: Salmon Arm, BC
I installed my TKO 600 almost that long ago with no modifications and it works beautifully. The only mods I am aware of involve the synchros as the trans has a bit of a reputation for not shifting smoothly. I did find the trans was a little challenging to shift when it was new, but after a couple thousand miles it smoothed right out. I probably have about 10,000 miles on it now and its smooth as silk. The only complaint I have is it leaks like the proverbial sieve. I have always added a couple hundred cc's of oil every season to keep it topped up. Last year I decided to put some dye in it to see exactly where it was leaking. Long story short, everywhere.
My tranny was just the same....a little notchy for the first 1000 miles and then smooth as butter since.
I bought mine through "ClassicChevy5Speeds"
Melting Slicks
Joined: Sep 2010
Posts: 3,280
Likes: 687
I put a 600 TKO in my 73 Camaro with a LS3. It was a bit notchy on the 2-3 shift. But I'm comparing it to the T56 Magnum I had in my 68 C10 LS swap. The TKO never leaked. I did have to mod the trans tunnel due to the fact the top of the 600 is kind square on the top.
Don't know if it's an option for you but the Tremec TKX 5 speed has become popular due to it's more compact size.
Don't know if it's an option for you but the Tremec TKX 5 speed has become popular due to it's more compact size.
Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
I have installed 2 TKO-600's. One in my 1973 Corvette and one in my 1955 Chevrolet. Both are great and have had no problems. I did damage the rear seal on the one in the Corvette during installation, Found a seal locally and both have been leak free. I got the .82 5th gear. I did the 55 Chevy first about 6 years ago and the 73 Corvette 3 years ago.
Thread Starter
Melting Slicks
Joined: Nov 2006
Posts: 3,396
Likes: 1,812
From: Apple Valley, MN
I put a 600 TKO in my 73 Camaro with a LS3. It was a bit notchy on the 2-3 shift. But I'm comparing it to the T56 Magnum I had in my 68 C10 LS swap. The TKO never leaked. I did have to mod the trans tunnel due to the fact the top of the 600 is kind square on the top.
Don't know if it's an option for you but the Tremec TKX 5 speed has become popular due to it's more compact size.
Don't know if it's an option for you but the Tremec TKX 5 speed has become popular due to it's more compact size.