TKX install/fitment question

[Wizbangdoodle]

I looked all over and couldn't find an answer for this.

I've installed my 408 with the Tremec TKX 5 speed. Was trying to install the transmission support bolts, but found that a tab on the tranny is hitting the e-brake bracket (see picture).

The manual covers a TKO and all my forum searches got me nothing. I'm hoping it's just "cut that tab off the transmission". 20240928_184853.jpg20240928_184735.jpg20240928_184722.jpg

[robmccon]

Correct! Easily removed mine with a sawzall.

[F500guy]

I got a super long blade so I did not even need to remove the transmission when I cut it off. That mount is not used.

[Wizbangdoodle]

Thanks guys. I knew someone here would have the answer. Not sure why they don't have that in the manual or an addendum.

[JMD]

Had the same issue myself. I was nervous using a sawsall so did it by hand with a hacksaw. Easy peasy. Isn't it nice when the solution is so simple??

[Rebostar]

fix in place, saw it off! I used a pnumatic minnie saw.
Happy Trails

[Wizbangdoodle]

It really is a simple solution, but when it comes to slicing things off the transmission, I wanted some reassurance that I was correct. Kinda disappointed that the manual I have does not show a TKX, only a TKO. It's been several years, I think it's time for an update.

[Jeff_J.]

Finding out afterwards is less fun!! So many different engine/trans options out there it's probably difficult to list all the special attention items. Thanks why the forum is such a great place to find out stuff.
Thanks again to all those who post their experience.!!

[Wizbangdoodle]

And now that everything lines up, my driveline angle is a bit extreme. Guess I'll have to use some spacers under the transmission mount.

[cv2065]

And now that everything lines up, my driveline angle is a bit extreme. Guess I'll have to use some spacers under the transmission mount.

Mike Forte makes a shimming kit.

[Jeff_J.]

Pinion angles - no lack of discussion on this topic. Sims are required in most cases - this is a good time to install a Metco driveshaft safety hoop if that's in the plan.

[Wizbangdoodle]

After messing around with it and trying different height spacers, (stack of washers) I need just over 1" of lift on the transmission.

cv2065, saw Mikes shim kit, but it doesn't state how much height it will give you. I've decided to make my own.

Jeff_J. I have read a number of these angle threads. There seems to be no end to the questions AND answers as to what's right. The video that someone posted on this was very telling. From what I can gather, the pinion and tailshaft need to be at the same angle, even if they are not in a direct line. As a matter of fact, it's best if they are not.

[cv2065]

I have his kit. I can measure if you need it.

[Jeff Kleiner]

… From what I can gather, the pinion and tailshaft need to be at the same angle, even if they are not in a direct line. As a matter of fact, it's best if they are not.

No. The front of the pinion needs to angle downward approximately 2 degrees IN RELATION TO THE TRANSMISSION OUTPUT.

It’s really quite simple yet continues to be baffling to so many builders.

Jeff

[Wizbangdoodle]

With an IRS, how do I "adjust" the pinion angle? I've looked at this for what seems like hours and the diff is a fixed position. Do you have a procedure you approach this with?
I know this has been covered ad nauseum, but I want to make sure I do it right the first time. I have read a number of threads on this subject and watched a few videos, mainly on drivetrain alignment theory. Jeff, since you've built a number of these cars, I'll defer to your expertise.

Just re-read your post and the "IN RELATION TO THE TRANSMISSION OUTPUT" is the answer. So, let's say the output shaft is pointing "up" 4*, the pinion would need to be up 2*. Am I looking at this right?

[Jeff_J.]

I have to admit the whole driveline thing confused the heck out of me at first, the whole up down thing & the terminology seems backwards at first, then the lightbulb went on and it became clear. Like Jeff K. said above there will be around 2 degree difference. Lots of info and diagrams on the forum as well as on google and Utube videos. One of the forum members suggested using the online "Spicer driveline calculator", it helped me determine the best angle I could get from my setup. I used washers first then made my own spacers. You'll get it, hang in there.

[Jeff Kleiner]

With an IRS, how do I "adjust" the pinion angle? I've looked at this for what seems like hours and the diff is a fixed position. Do you have a procedure you approach this with?
I know this has been covered ad nauseum, but I want to make sure I do it right the first time. I have read a number of threads on this subject and watched a few videos, mainly on drivetrain alignment theory. Jeff, since you've built a number of these cars, I'll defer to your expertise.

Just re-read your post and the "IN RELATION TO THE TRANSMISSION OUTPUT" is the answer. So, let's say the output shaft is pointing "up" 4*, the pinion would need to be up 2*. Am I looking at this right?

OK, since I don't know what your definition of "output shaft is pointing up" is lets just use this diagram that I made about 10 years ago. You know how they say that a picture is worth a thousand words


You can rotate this any way you like so that the output points up or down---the relationship between the trans output and the differential pinion still needs to be the same, with about a 2 degree difference.


As far as the pinion in an IRS being in a fixed position, you are correct. Since you can't change that you have to change the angle of the output shaft by adjusting/shimming the rear of the trans up or down. In reality the pinion angle isn't especially critical in an IRS car since the driveline doesn't move or change like it does in a live axle car nor does the load on the differential allow the front of the pinion to rotate upward.

Does that help?

Jeff

pinionangle.JPG

[JJK]

Building off of what wizbang noted, it is pretty typical with the tkx and irs to shim the trans tail, somewhere in the range of 0.75"-1.25" seem common

[Wizbangdoodle]

OK, since I don't know what your definition of "output shaft is pointing up" is lets just use this diagram that I made about 10 years ago. You know how they say that a picture is worth a thousand words


You can rotate this any way you like so that the output points up or down---the relationship between the trans output and the differential pinion still needs to be the same, with about a 2 degree difference.


As far as the pinion in an IRS being in a fixed position, you are correct. Since you can't change that you have to change the angle of the output shaft by adjusting/shimming the rear of the trans up or down. In reality the pinion angle isn't especially critical in an IRS car since the driveline doesn't move or change like it does in a live axle car nor does the load on the differential allow the front of the pinion to rotate upward.

Does that help?

Jeff

pinionangle.JPG

That's what I was understanding. My written skills are lacking. And as you say, a picture is worth...

That picture describes how I have it setup, although I'd say my pinion was flat and the tailshaft is 2 degrees down. Rotate that picture clockwise and you have my setup. So, I think I'm good. Thanks Jeff and everyone else. It has been a good day at school.

[JMD]

I've been adjusting this for the past couple of days on my build. I have the 302 with FFR supplied engine and tranny mounts with the TKX. I used (3) 1/4" shims supplied by Forte on top of the transmission mount but got a noticeable vibration. I added two thick hardened washers on each side, raising it another 5/16" (total of 1 1/16") and it was better, but still noticeable. My driveshaft went from 2.5 degree up angle to 2.3 degree down angle with this adjustment. I removed one of the washers (now at a hair over 0.9") and it is a lot better. My down angle on the engine is 2.6 degrees, my driveshaft is at 0 degrees, and my diff has a down angle of 0.3 degrees. (All angles measured in relation to the frame.) Total angle in relation to driveshaft is 2.3 degrees but I think that's as good as I can get it without changing motor mounts. I wonder whether there's room to add a washer in front of the top diff mounts to increase the down angle...that would probably put me within the 2 degree specification.

IMG_4187.jpg

Sorry for the unasked for info...just got done messing with it yesterday so it's still fresh. Hope it's helpful.

[Wizbangdoodle]

I've been adjusting this for the past couple of days on my build. I have the 302 with FFR supplied engine and tranny mounts with the TKX. I used (3) 1/4" shims supplied by Forte on top of the transmission mount but got a noticeable vibration. I added two thick hardened washers on each side, raising it another 5/16" (total of 1 1/16") and it was better, but still noticeable. My driveshaft went from 2.5 degree up angle to 2.3 degree down angle with this adjustment. I removed one of the washers (now at a hair over 0.9") and it is a lot better. My down angle on the engine is 2.6 degrees, my driveshaft is at 0 degrees, and my diff has a down angle of 0.3 degrees. (All angles measured in relation to the frame.) Total angle in relation to driveshaft is 2.3 degrees but I think that's as good as I can get it without changing motor mounts. I wonder whether there's room to add a washer in front of the top diff mounts to increase the down angle...that would probably put me within the 2 degree specification.

IMG_4187.jpg

Sorry for the unasked for info...just got done messing with it yesterday so it's still fresh. Hope it's helpful.

Glad to see you got yours under control. If you need more room for tweaking, you can always shim the motor mounts and see what that gets you.