Tremec TKX vs Toploader with a Gear Vendor

[Rory428]

I currently have the 428 from my 59 all apart, and since the Toploader 4 speed is also out, considering something better on the freeway. My normal rear is a 31 spline Detroit Locker, which I want to retain. Since many of the events around here require at least an hour or more of freeway speeds, I want to have something with overdrive. I am mostly considering either a new Tremec TKX 5 speed, or adding a Gear Vendors overdrive unit to my existing toploader , which is a small spline wide ratio unit. Both the TKX and GV are pretty close in price, although the TKX will require an adapter spacer to use my factory bellhousing, plus a new clutch disc, and possibly a different shifter to avoid cutting a different hole in the tunnel, and a new carpet set, as well as modifying the trans crossmember and mount, and possibly the floor/tunnel to make it fit. I also want to keep my factory mechanical clutch linkage. Has anybody actually install a TKX in their FE powered vehicle, and have some real life driving impressions, and advice on what needed to be modified to fit in an older car.
Also interested in hearing any similar impressions about a Gear Vendors unit, for fitment and function. The car is mainly a street car, but will see dragstrip duty, with slicks, at least twice a year.
Perceived pluses for the TKX is a brand new transmission, likely a bit lighter, plus the Toploader could be sold to help offset the cost of the TKX, or used in another car, but having heard how other Tremecs don`t like full throttle power shifting at the track is a concern, as is concern over shifter position, possible floor cutting, trans mount fitment, and the need for a new clutch, or at least, a new disc.
I love the way my Toploader shifts, how the Hurst Super Shifter looks , plus I already have it, and it works well. But I have to wonder if the Gear Vendor will require tunnel/floor surgery, if the extra length behind the trans crossmember will cause issues with driveshaft /pinion angle issues, and require modifying my existing exhaust system to make it fit. Anybody have any thoughts on either, or both scenarios?

[The Real McCoy]

I installed a TKO 600 Tremec in my 63 Galaxie with a 428 about 4 years ago.  I absolutely love the way it drives and shifts compared to the BW T10 that was in it.  My car does not see dragstrip duty so I can't comment on that.

I did have to do some work to the tunnel to make it clear, I would expect less or no work would be required for the TKX transmission to clear.  The T10 shifter is mounted to the left side, as is your toploader shifter, where the Tremec's are mounted directly to the top so it would seem you would have a very hard time not redoing your shifter hole.  I wasn't crazy about cutting up the floor pan but the reality is after fabricating and securing the new metal it is absolutely undetectable other than someone nit picking that the shifter is in the center rather off to the left side.  My TKO 600 had a fore, center, and aft shifter location. I used the center shifter location which might put it a little too close to the dash for a drag racer but it works well for me.  The aft shifter location could create a conflict on a bench seat car, you just need to closely evaluate what works best for your car.

 On my TKO 600 I was able to use a FE pickup bell housing which eliminates the requirement of the adaptor that you mention. This bellhousing is about 5/8" deeper which accommodates the longer input shaft on the Tremec transmission.   The bellhousing has "C5T" prefix on the casting number and was used from 65-?? on FE powered F series pickups.  Pretty easy to find and reasonably priced.  I have the exact part # somewhere if you need it.  A possible caveat is my 428 has a Scat stroker crankshaft which has 2 holes for the pilot bushing/bearing.  I used the large bronze bushing that goes into the largest of the 2 holes in the very rear of the crankshaft for the BW T-10 transmission.  There is a smaller and deeper hole (toward the front of the crankshaft) that accepts a pilot bearing (smaller diameter) that was used for the TKO 600.  The problem MAYBE is I'm not sure if ALL crankshafts have this smaller hole to accept the pilot bearing.  In any case you need to be careful that your crankshaft thrust end clearance is maintained during final assembly.

With the above mentioned bellhousing I was able to maintain my factory mechanical clutch linkage.

I do have an extensive write up and lots of pictures of the TKO 600 installation as it pertains to my 63 Galaxie that I could share with you if you're interested in reviewing.  It's on a Word document and is quite lengthy so it would best to be emailed to you.  I would expect some of it would apply to your 59 Galaxie.  Let me know if you would like to review it.

Whatever route you choose I'm sure you will love having the overdrive.

[jayb]

Rory, on the Gear Vendors side they are a super strong unit, but the overdrive is only 0.82:1, so I think the TKX would have a better overdrive ratio.  I have three of the Gear Vendors units and I really like them for high HP applications but I'd probably lean towards the TKX for a lower HP vehicle. 

Also for what it's worth, I found it interesting that the Gear Vendors unit fit in the tunnel of my 69 Mach 1 with no issues, but that I had to cut the floor of the Galaxie to make it fit.  I don't know if you would have to cut your 59, but if the tunnel shrinks down under the front seat like it does on my Galaxie, that would probably be necessary. 

Hope that helps - Jay

[Rory428]

Jay, on my 59, the tunnel is pretty low, and also tapers even lower around the front seat, so chances are my floor would need similar surgery as your 64 did, for the Gear Vendor. The tunnel is much lower than my 69-70 Mustangs were, I guess the weak little 3 speed manuals and automatics back then didn`t take up much room, so the tunnel was lower, plus, back then, 3 across seating was also common, so legroom was important.
As for the overdrive ratios, the TKX I am considering is almost identical to the GV, a 0.81 5th. They also offer a 0.68, which in my opinion would put the freeway RPM to low for my carbed 428 , about 1700 at 60 MPH. They also show a 0.72, which would be best, but that is only available with a 3.27 1rst gear, which is way lower than I want. (The other 2 versions have 2.87 low gear.)  Thanks,

[Joe66GT]

   Rory, I put a TKX in my '66 Fairlane. Close ratio with .68 5th. The car has a 4.11 rear with 275/60-15 tires. I wound up cutting the tunnel just behind the shifter and welding in a small bump up to get more clearance for the shift rail casting at the back of the transmission, the shifter stayed in the factory location with the Lakewood scatter shield and aluminum spacer.
   The TKX trans mount is further back compared to the top loader and as a result the factory cross member would hit my X pipe. I fabbed up a new cross member rather than cut up the factory piece. Kept the factory clutch linkage and replaced the speedo drive gear with I think a 21 tooth gear and opposite rotation from the top loader gear.               

   The overdrive was a dramatic change from the old top loader on the highway! The shifter has a very positive feel to it, notchy until you put some heat into the transmission. After that it seems the faster you spin it the better it shifts. Oh and I had to have a new, longer, drive shaft made. Joe.

[TomP]

There is a smaller and deeper hole (toward the front of the crankshaft) that accepts a pilot bearing (smaller diameter) that was used for the TKO 600.  The problem MAYBE is I'm not sure if ALL crankshafts have this smaller hole to accept the pilot bearing.

A stock 428 does. I adapted a Dodge truck tranny to my ramp truck years ago doing that.  The splines went right where the normal pilot bushing sat . I used an Oilite bushing 3/4" ID and whatever the OD was  (1 1/4?) and I cut off a bunch of the Dodge pilot tip. Also had to cut the throwout bearing collar down to clear the disc.
 I'd imagine adapting a too long Tremec could be done like that to avoid a spacer.

 The Gear Vendors has the advantage of being able to be used in all gears. Not much benefit with a Toploader but i've got one for my T19 in the ramptruck to narrow those ratio spreads some more.

1700rpm cruise sure doesn't work very well for carb'd cars with any sort of a cam. My Cyclone is terrible for that with 3.00's and 29" tires. I need to just watch for cops and pass everyone or use third to avoid surging.

 

[Rory428]

   Rory, I put a TKX in my '66 Fairlane. Close ratio with .68 5th. The car has a 4.11 rear with 275/60-15 tires. I wound up cutting the tunnel just behind the shifter and welding in a small bump up to get more clearance for the shift rail casting at the back of the transmission, the shifter stayed in the factory location with the Lakewood scatter shield and aluminum spacer.
   The TKX trans mount is further back compared to the top loader and as a result the factory cross member would hit my X pipe. I fabbed up a new cross member rather than cut up the factory piece. Kept the factory clutch linkage and replaced the speedo drive gear with I think a 21 tooth gear and opposite rotation from the top loader gear.               

   The overdrive was a dramatic change from the old top loader on the highway! The shifter has a very positive feel to it, notchy until you put some heat into the transmission. After that it seems the faster you spin it the better it shifts. Oh and I had to have a new, longer, drive shaft made. Joe.

Joe, thanks for the real world experience, I assume the spacer/adapter is about 1" thick? Although I still have a Lakewood scattershield, I will probably keep my current early narrow pattern (1961) iron bellhousing, since the early bells clutch fork works with my clutch linkage, and the later bellhousings have the clutch fork angled down more buy over an inch. So I will need a spacer that also adapts from the narrow pattern to the TKX. Since I plan to keep the 3.50 gears, I would likely chose the 0.81 OD, the  0.68 is a bit too much reduction. The 0.81 should put me around 2000 RPM at 60 MPH.  Did you have any issues retaining the factory clutch linkage, and did you need to cut the tunnel for the main case at all, or just for the shifter area?

[My427stang]

I haven't had a TKX apart, but on a TKO you can pull the input shaft without taking the tranny down like a toploader.  Very quick work to cut the input shaft length and spline length to exactly the Toploader dimensions.  Might gain you room being farther forward and then it's just a clutch disk change, TKX may be the same.

FWIW, I have 16 years on my TKO600 with a .64, love it as much as day 1, both OD and overall gear spread.  I have a cut input and Lakewood. My best buddy with a 68.5 CJ has a TKO, same attitude, loves it, has a spacer and factory CJ bell, and one of my CJ stroker customers did a TKX with a CJ bell and didn't have to do any shaping on the floor, I haven't heard how he liked the tranny, but I expect he does a lot. I think he used a spacer too

The only downside of these 5 speeds is, 3rd isn't all the way over and up.  When you first get it, it's sort of gated/spring loaded, but when you first get it, you'll see how you are used to finding 3rd, and you'll end up in neutral between 3rd and 5th, feeling like a rookie.  I don't notice it now, but they make shifters with more solid gates if you find you need it. 

It also uses a stock Ford speedo cable, although on the other side, easy for a Mustang just use a C4 version, has a backup light switch built in which works very nice

[TJ]

I believe the gear vendor is 0.78:1, fwiw. 

Also, the electronic controller that comes with the gear vendor will not let you use it in all gears.  The output shaft has to spin a minimum speed to build enough fluid pressure or it won't shift to overdrive.  I guess that could be bypassed so you could have overdrive in the lower gears and even reverse but that would likely wear on the gear vendor.  Not sure how TomP gets the gear vendor to shift in all gears with the T19.  I can only use it in 3rd and 4th which happens to be where I need overdrive for towing.

I really like the gear vendor behind my np435 in my pickup though I would prefer a 5 speed or better yet a 6 speed if I could find one to mate to my FE with the gears I want so I could have just one gear box instead of two.  The tremecs would be great if I wasn't towing anything...their 1st is too fast.

[2ndgear]

Little Info on my 4-speed and gear vendor. I can push the button whenever I want to and it will shift into the high side of the gear I am in. It also has a launch control on it which I dont really use. The other thing is if you want to sell it some day you can sell it to anybody. Can be Dodge or chevy also. All they have to do is buy the tail housing adapter,everything else is the same. The over drive is great for engine RPM and gas mileage. Hope this helps some. Car is 69 mustang with no tunnel mods. at all.(lucky I guess)

[fairlaniac]

I went from a Toploader to a TKX in my '66 Fairlane. At time and I'm still not sure if they have them. A FE input shaft did not exist. I had a Lakewood bell housing. So I bought a QuickTime bell. I used the space blocks that come with the QuickTime to position my fork in the same location as the Toploader. So I did not need to alter my linkage. With the TKX and bell combo I did need to shorten my driveshaft by 3/4". Unlike Joe's installation. I just rotated my OEM trans mount 180 degrees and the factory type isolator mounted perfectly. For some reason my trans angle changed so I made a 3/8" thick spacer between the isolator and the trans. I did not need to make any modifications to the tunnel. You'll need to purchase a reverse switch that fits the TKX and mate the wires appropriately. I used a small block fork and t/o bearing. If they still only have the GM splined input you'll need a new clutch disc at a minimum. I seem to remember the pilot bearing being the same? That I cannot say with 100% certainty?

Overall I like it very much. Not that I worry much about gas mileage, I can now at least get to a destination and home on the same tank of gas.

[Joe66GT]

   Rory, the spacer was 5/8ths of an inch thick. I contemplated shortening the input shaft but combined with the Lakewood the spacer put the shifter in the factory location.  Clutch linkage remained stock but I had to get a small input clutch fork, the top loader was a big I/O.
   No other modifications were needed for the tunnel and the factory mount does bolt up and mine came with a back up light switch. 2000 rpm's puts me at 60 mph with my gearing.
   Funny thing though is that it's advertised as having all 5 carbon faced blocker rings but mine came with bronze faced blockers on first and second? The input shaft doesn't come out through the front like the 600.  Joe