Drive Shaft

[mbisett]

I have been trying to install the driveshaft and wanting to know what the trick is. I have the new TKX transmission and IRS. I noticed a notch on the spline end of the drive shaft but can’t seem to locate a notched spline on the transmission spline - am I missing something?

I have had the driveshaft neck inside the rubber boot (no easy task itself) and rotated the drive shaft all the way around as straight as possible but I can’t get the spines to marry.

I must be missing something.

Thanks in advance!

[Railroad]

I think the notch is actually a missing spline. It does not affect orientation of the yoke and the spline. The TKO transmission had a rubber donut just inside the rear seal on the tail shaft.
I have read that it can be pushed in as the yoke is installed, but I had to remove the donut to get the yoke to accept the tailshaft.
A little lube, as trans fluid, motor oil etc will help. Wet the splines inside the yoke.
I had to use some long needle nose pliers to remove the donut. Do not damage the seal. Wetting the seal will also reduce abrasions from removing the donut.
The yoke must be aligned straight.

[mbisett]

Thanks for the guidance! I will try it that way tomorrow. I really have an issue with getting it straight enough to slide on the shaft so removing the rubber may get me there. Fingers crossed.

[mbisett]

Tried everything possible and there is simply not enough room to get the drive shaft aligned straight enough.

I am now thinking about breaking down one of the universal joints to get it installed. I am just not sure that I can manage to put it back together under the car. Any guidance would be appreciated,

[rich grsc]

Put the shaft above the reared on the right side, not from below. DO NOT try to take the u-joint apart, you will not get it together under the car

[mbisett]

Thanks for the feedback. I will give it another try from above the rear end.

[michael everson]

Also don't be afraid to take the bolts out of the mount and move the trans up a bit.
Mike

[steno]

You beat me to it Mike!

[Bob 5.0]

I had fun with mine to ! As mentioned already put the tail end of the drive shaft in above the diff left or right which ever gives you the most room then slide the yoke in the trans and make sure your trans is in gear !
Bob

[mbisett]

Update. I have tried about everything mentioned on this thread and even pulled the engine/transmission back out and still can not get the drive shaft inserted in the transmission! I am thinking I have the wrong drive shaft it is a 31 spline.

I have a call into Blue Print to help solve this issue.

[rich grsc]

Are the spline counts different for the new TKX, different diameter?

[NAZ]

Count your trans output shaft splines, should be 31. If you have a blank spline on your slip yoke it counts as a spline. Count the number of actual splines then add one for the blank.

[Hoooper]

None of the TKX transmissions are listed as 31 spline https://www.tremec.com/menu.php?m=184

[NAZ]

None of the TKX transmissions are listed as 31 spline https://www.tremec.com/menu.php?m=184

Try this: https://www.moderndriveline.com/shop...-spline-input/

[Hoooper]

Try this: https://www.moderndriveline.com/shop...-spline-input/

Hahaaaa, the column I was looking at says input splines

[edwardb]

TKX output spline count is 31. Same as the TKO.

[mbisett]

After hours and hours (even pulling the engine/transmission out) and speaking with BP techs and FF techs I decided to research the Tremec website and found the solution! The splined plug on the tailshaft is for shipping and supposed to slide forward when inserting the drive shaft (mine wouldn’t) - IT IS NOT NECCESSARY and can be removed, which I did and the driveshaft slipped on as expected. What a waste of time and patience. Hoping others can learn from this and skip this bs in the future.

[mbisett]

Railroad - I did not totally grasp your guidance above but learned the hard-way to trust instructions from those that ha=e then knowledge, even if it might be a different vintage engine/transmission issue. It really cost me a lot of time and energy! Thanks so much for your guidance and sorry that I did apply it to my application (TKX vs TKO).

[txboiler]

mbisett.

I am prepping to install the driveshaft and I have the TKO600. If I am filling you correctly the splined “donut” on the output shaft can be removed? How hard did you have to pull to get it out? I have tried pinching it and pulling it out but could not. Before I grabbed with piers and tried pulling it out I wanted to make sure I am facing the same challenge. My “donut” is about a 1/4” proud of the rear seal.

184C13A0-0191-46BB-AD20-EE1C9081A243.jpg

[NAZ]

Yes, it will pull out.

[mbisett]

I used needle nose pliers and was careful to not damage the rear seal. I pulled it out very slowly but it was really easy.

[Souleman]

Just ran into this little guy. Exact same issue! Spent about an hour wrestling with the driveshaft and cursing at it. Discussed with my son the option of pulling the engine, but we both agreed to search the forum first. Thanks guys for the wealth of knowledge! Pulled the stupid shipping “donut” and it slid on beautifully. Not sure how it would slip forward, but could almost see how you might be able to place it far back on the driveshaft then once the drive shaft is on and sliding forward, slide it back into position under the main seal…my son thought that sounded like way too much effort��

[Souleman]

Which bolts did you use for the drive shaft? My instructions say use the bolts that came with the drive shaft (mine came with none from FFR). I have a set of 4 M10 X 20MM socket heads in my hardware box that look correct.
IMG_8075.jpg

[Souleman]

Just to close the loop, I emailed Dan at FFR and yes, the M10x20mm or the M10x25mm socket heads can be used. On my set up, the M10x25mm look just a tiny bit too long though.

[Sixflyer]

I’ve been following your thread on your driveshaft as I get ready to address that on my mark 4 build. FFR said they had no driveshaft for my 4.6 DOHC/TKX/IRS configuration in spite of it seemed to be the last one on the list of options. My distance from the IRS flange to the back of the TKX is about 11 inches and that shaft is 10.5 but Jeff at FFR said it would not fit but didn’t say why. 31 spline output on the trans. Any measurement you can give me on your might help me figure this out. Thanks in advance.

[Jpruss221]

Just to close the loop, I emailed Dan at FFR and yes, the M10x20mm or the M10x25mm socket heads can be used. On my set up, the M10x25mm look just a tiny bit too long though.

I connected my drive shaft this week and ran into an issue with the socket head bolts FFR provided. The socket heads are approx. 020 too large and won't fit the the recess holes for the adapter plate. I had to go to Ace hardware and pickup low profile socket heads with smaller diameter. These are grade 8 bolts which i'm not certain the FFR bolts are grade 8. I also did not receive the 12pt 10mm bolts which should have come with the driveline as stated in the manual. Good luck

[BRRT]

A lot of us have an issue with the counterbore in the driveshaft adapter being a little small for the socket head screws FFR provides. Some use a lathe to turn them down, I used my drill and a file. Spin them up in the drill, hit it with the file until they fit.
Don't forget to loctite them during installation.