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12/20/2021 3:48 PM  #1


T5 Compared to a TKX For a Classic Ford

Just a little somthing I threw together.



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12/20/2021 4:21 PM  #2


Re: T5 Compared to a TKX For a Classic Ford

 

12/20/2021 4:26 PM  #3


Re: T5 Compared to a TKX For a Classic Ford

Nice video Daze.  I'll toss a little more info out there that I know about the T5 and TKX. 

With G-Force or Astro gears you can build a T5 to last behind 500 lbs/ft. in a 3,500lb car with sticky tires and a reasonable clutch.  Cost is going to be close to a TKX, but you can use a stock T5 bellhousing, the good shifter you presumably already had on the T5, etc. 

Don't get hung up on torque ratings.  The test used to determine this is to lock the trans in 1st gear and shock load it until it breaks.  The 3.35 first gear T5s are going to seem weaker in this test because of the leverage the large first speed gear puts on the small gear on the countergear.  This test effectively only shows what a trans will survive shock loaded in 1st gear.  After dozens of T5 rebuilds and transmissions I've built used in all kinds of racing I've yet to see a broken 1st gear in a T5.  3rd gear is the most commonly broken gear and its essentially the same across all T5s.  The later model T5s and the Z-spec transmissions in theory have 2nd and 3rd gears made from a better alloy (often called "double moly" because I think they are supposed to use twice the molybdenum content in the alloy).  In practice I've not seen this make them significantly stronger.  However, the reason 3rds gear breaks is simple: traction.  In a reasonably powerful street car you simply lack the aggressive clutch, sticky tires, and suspension to break anything because the tires will go up in smoke first.  By 3rd gear you usually have traction unless you're making 500+HP or are using a power adder. 

More often than not T5s are broken from abuse, not weakness.  If your clutch doesn't fully release, if you do a lot of sloppy powershifts, etc. what happens is the 3/4 slider gets hung up going into 3rd and something breaks. 

Also, T5s are getting old now.  Gears lose their hardness over time from being heated up and slowly cooled in oil.  The oldest ones are now at about the point the musclecar transmissions were when I first started rebuilding transmissions.  We used to see all kinds of failures in those we shouldn't have because the gears simply weren't hard anymore.  The heat treat controls and steels used by the '80s and '90s were better than in the '60s and '70s, but its going to become more and more of a problem over time I'm sure. 

Now, the TKX is the bees knees.  Its Tremec's best 5 speed, no doubt.  It incorporates everything they learned from the T5, TKO, etc. over 30 years.  There's also a fair amount of Tremec 3650 in it, which is another viable, lower cost option for a swap than the TKX.  However, there's literally no downside to the TKX other than cost. 
 

Last edited by TKOPerformance (12/20/2021 4:28 PM)

 

12/20/2021 10:50 PM  #4


Re: T5 Compared to a TKX For a Classic Ford

So, if I want a TKX, I need to -  get a different bell housing, different yoke, rebuilt drive shaft, change my z-bar to cable/hydraulic clutch mechanism. new clutch disk, and different u-joint.  Then I must modify that funny crossmember that goes over the trans hump.  He said nothing about the reverse light switch and shifter mechanism.  What does that add to the cost? 

Sounds like a normal hot rodding upgrade.

BTW that video from DAZE is great.  Well done.

Last edited by lowercasesteve (12/20/2021 10:52 PM)


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12/21/2021 9:36 AM  #5


Re: T5 Compared to a TKX For a Classic Ford

At this point, yes.  My guess is eventually someone will make an adapter plate for the TKX that will allow you to use a standard bellhousing and clutch setup. 

Reverse light switch is just a typical switch that breakers ground, so worst case you may have to change the terminal ends or lengthen/shorten the wires.  Shouldn't be a big deal.

Shifter wise its a typical Tremec internal rail shifter, but its different than the T5 or I believe any other Tremec thus far.  The aftermarket is already offering some options, but no Pro 5.0 yet, and IMO Pro 5.0 is the gold standard in shifters for Tremec transmissions. 
 

 

12/21/2021 10:17 AM  #6


Re: T5 Compared to a TKX For a Classic Ford

TKOPerformance wrote:

At this point, yes.  My guess is eventually someone will make an adapter plate for the TKX that will allow you to use a standard bellhousing and clutch setup. 
 

Its already available.  It uses a TKO bellhousing soooo a TKO adapter plate will convert the 4-speed bell into a TKO bell.  I am not a fan of adapter plates because the old school bellhousing can have a as much as a .035" tolerence where as modern transmissions reguire .005" or less.  Yes you can shim the adapter or use offset engine dowels but it is not the "right" way to do it IMHO

TKOPerformance wrote:

Shifter wise its a typical Tremec internal rail shifter, but its different than the T5 or I believe any other Tremec thus far.  The aftermarket is already offering some options, but no Pro 5.0 yet, and IMO Pro 5.0 is the gold standard in shifters for Tremec transmissions. 
 

TKX comes with the shifter and it seams to be a good one.

 


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12/21/2021 12:04 PM  #7


Re: T5 Compared to a TKX For a Classic Ford

IME any bellhousing used for racing needs to be indexed, or at the very least checked for runout.  It will only be an issue trying to shift into 4th at high RPM, so you'll be running pretty fast to need 4th on a 1/4 mile track.  Of course, if you're running that fast you're using a scattershield or you aren't running for very long because once the techs figure it out they will bounce you out the gate.  Long story short, yes, I'd also rather see a dedicated aftermarket bellhousing with the TKX pattern that accepts a standard clutch, be it cable, Z-bar, etc. than use an adapter plate and a bellhousing for something else.  I think give it some time and Quick Time or someone will make one.  Now, on the street it probably doesn't matter.  How often are you snatching 4th at 6,000RPM?  Hopefully not a lot, but wait, you do live in Montana, right?

The stock Tremec shifter is going to be better than say a stock shifter from a Fox Mustang (it would be a real task to try and make it worse), but its still Pro 5.0 and then everyone else and its not terribly close IMO.  Good that it comes with one though, given the price of a TKX. 
 

 

12/21/2021 3:18 PM  #8


Re: T5 Compared to a TKX For a Classic Ford

TKOPerformance wrote:

 Long story short, yes, I'd also rather see a dedicated aftermarket bellhousing with the TKX pattern that accepts a standard clutch, be it cable, Z-bar, etc. than use an adapter plate and a bellhousing for something else.  I think give it some time and Quick Time or someone will make one.  Now, on the street it probably doesn't matter.  
 

Again it is already being made.  That is one of the smart things they did when they designed this trans.  From the mounting flange up it is identical to a TKO so any aftermarket bellhousing or scatter-shield for the TKO is going to work with this transmission

TKOPerformance wrote:

 
The stock Tremec shifter is going to be better than say a stock shifter from a Fox Mustang (it would be a real task to try and make it worse), but it's still Pro 5.0 and then everyone else and it's not terribly close IMO.  Good that it comes with one though, given the price of a TKX. 
 

I have always run an eBay knockoff performance shifter on my T5(s) and have been very happy with them.  at least 10 times better than the foxbody OEM shifter.  I am sure the shifters I have are not as good as the Pro 5.0 but outstanding for a street car.  I say all this because the shifter that came with the TKX is comparable to the aftermarket shifters I am running on my t5(s)


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12/21/2021 5:33 PM  #9


Re: T5 Compared to a TKX For a Classic Ford

Okay, so massive confusion on the bellhousing.  If the TKX is the same as a TKO then there are already stock type aluminum and steel scattershields available that allow you to run whatever clutch setup you want.  However, it is an added expense unless you are upgrading from a TKO (why?). 

A bread stick in a bowl of linguini would be better than the Fox shifter, so yes, anything is basically an improvement.  Just removing the rubber damper in the stick mount is a major improvement.  The problem with most aftermarket shifters is they rely too much on aluminum and wear out eventually.  In a low use toy its usually not an issue, but the Pro 5.0 on the T5 in my '67 for example did 100k in my buddy's '95 Cobra before he gave it to me after converting to a Tremec 3550 (yep, before the TKO existed).  All I did was clean all the old grease out of it and regrease it with silicone grease.  There was no wear on anything.  They are basically bulletproof and last forever, though like most stuff that will do that, not cheap.  To each his own. 
 

 

12/21/2021 5:53 PM  #10


Re: T5 Compared to a TKX For a Classic Ford

Here is the shifter that comes with it.


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12/21/2021 6:20 PM  #11


Re: T5 Compared to a TKX For a Classic Ford

What's under the magic boot?

 

12/21/2021 6:30 PM  #12


Re: T5 Compared to a TKX For a Classic Ford

TKOPerformance wrote:

What's under the magic boot?

Don't look behind the curtain 😂

Honestly I am not sure, I have not investigated yet and I currently have the transmission boxed up and put away while I wait for my engine to come back from the machine shop... Some time in February after I get them my stroker kit for balancing but the kit is on backorder.  Anyway I don't see any positive stop adjustments like my billet T5 shifters have but I guess there could be set screws under the boot.  Will report back the next time I pull it out.
 


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12/21/2021 6:39 PM  #13


Re: T5 Compared to a TKX For a Classic Ford

TKOPerformance wrote:

  If the TKX is the same as a TKO then there are already stock type aluminum and steel scattershields available that allow you to run whatever clutch setup you want.  However, it is an added expense unless you are upgrading from a TKO (why?). 
 

Exactly no one is going to replace a TKO with a TKX unless the issue they are having with the TKO is max RPMs, BUT because the T5 and the TKO use the exact same bellhousing casting with only a different mounting pattern, if a person is setup to TIG aluminum they could weld closed the T5 bolt holes and then drill and tap the TKO mounting pattern.  


TKOPerformance wrote:

A bread stick in a bowl of linguini would be better than the Fox shifter, so yes, anything is basically an improvement.  Just removing the rubber damper in the stick mount is a major improvement.  The problem with most aftermarket shifters is they rely too much on aluminum and wear out eventually.  In a low use toy its usually not an issue, but the Pro 5.0 on the T5 in my '67 for example did 100k in my buddy's '95 Cobra before he gave it to me after converting to a Tremec 3550 (yep, before the TKO existed).  All I did was clean all the old grease out of it and regrease it with silicone grease.  There was no wear on anything.  They are basically bulletproof and last forever, though like most stuff that will do that, not cheap.  To each his own. 
 

This is basically what I am using (with the positive stops installed) and yes it is aluminum but neither of my cars are seeing that many miles especially the Mustang it has not been on the road in quite some time.  I totally get what you are saying and see the advantage to a superior shifter especially for high use applications.


 


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12/21/2021 9:21 PM  #14


Re: T5 Compared to a TKX For a Classic Ford

Nice video DAZE


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12/22/2021 8:17 AM  #15


Re: T5 Compared to a TKX For a Classic Ford

I would be surprised if it has stops built in.  I've never seen a factory shifter that has them, or they may be there, but not adjustable.  There's a first time for everything and the TKX IS a new design, or the TKX may not need them.  I've never seen one apart, so its possible there are stops inside the transmission.  Stops are like anything else with the Tremec line of transmissions from the T5 on up.  Basically the shifter stops are used so you can abuse the transmissions without fear of breaking a shift fork.  The only time you are going to put enough force on a fork to flex/bend it is by slamming the trans into gear.  There's also debate about what really causes the forks to break.  A lot of guys claim its the force on slamming the trans into gear and the fork being able to flex from being able to move too far toward the gear you're going into after the slider stops moving.  But some guys say there's no way that's possible.  First, there is some measure of stop inside the trans in the detent assembly.  Second, the amount of flex needed to cause failure in the fork just isn't possible.  So the alternate explanation is that the clutch isn't being fully released due to bad pedal technique or improper adjustment.  This means you are shifting with some load still applied to the parts you are trying to take out of one gear and put into another.  This causes resistance and you get binding in the hub/slider assembly.  On rare occasions this can break the synchro keys and there are billet keys available for the T5 to prevent key breakage.  The other possibility is that this is what's causing the fork flex that eventually leads to a failure.  In the middle of the travel there's no stop to prevent damage, and in a fist fight steel is going to beat aluminum most every time (the fork is the weak link).

I don't know who is right here, and my guess is that both arguments have merits as they are espoused by top guys in the industry.  What I can say is that I've never pulled a broken fork out of a T5 that had a shifter with stops, so IMO regardless the reasoning the stops do seem to prevent fork failure. 

The alternate solution is forks made from better material.  G-Force has solid bronze forks available for the T5, and Hanlon has billet forks for the 3650.  The TKX forks from what I've seen are much heavier duty than the T5.  They look like T56 forks.  However the 3/4 fork in the T56 was deemed a weak link and Viper spec T56s used a steel fork often installed as an upgrade in other T56s at rebuild/repair time.  My thoughts are usually an ounce of prevention is worth a ton of cure, so if a shifter with positive stops was available I'd upgrade.
 

 

1/12/2022 2:07 PM  #16


Re: T5 Compared to a TKX For a Classic Ford

I just saw this on a "speed show" They put a TXK in a 67 cougar using an aftermarket kit. The kit's solution to not having to notch the floor support was a lower mounting crossmember (increasing transmission angle) and to have the trans right up against said tunnel support. I am beyond horrified.
 


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1/12/2022 3:24 PM  #17


Re: T5 Compared to a TKX For a Classic Ford

Yeah, bunch of hacks and morons on most of those shows sadly. 

 

1/12/2022 3:27 PM  #18


Re: T5 Compared to a TKX For a Classic Ford

TKOPerformance wrote:

Yeah, bunch of hacks and morons on most of those shows sadly. 

Sadly I can't blame it on the host, It wasn't there work that was the problem.  They purchased a kit from a reputable aftermarket company that makes the TKS a "bolt in" on a Mustang or Cougar and it was that companies solution to mount the trans incorrectly.


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