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XL18 transmission additive - where to find?

I stopped at my local dealer to get some XL18 but it is unavailable. It is in their computer system but no source info listed and no promise date for delivery. If any vendor has some to sell, let me know. Heck, if anybody has any left over with enough in a bottle for one dose, let me know.
 
Thanks. I found the XL18 on Fordparts.com but it shows 0 quantity available at AutoNation Ford as well as a few other dealers I selected.
 
Thanks again. I called (formerly) Tousely and ordered it. It will be a few weeks because they have to order it from their supplier then ship it to Canada for me. That's all good because winter is just about here and Boss season is pretty much over. I'll be ready for spring.
 
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I read that all Mustangs built after 7/9/2012 already have the additive.

http://www.allfordmustangs.com/forums/2011-mustang-gt-tech/541546-mt-82-transmission-additive-update-9-print.html

Post number 5 on the page above
 
JB said:
I read that all Mustangs built after 7/9/2012 already have the additive.

http://www.allfordmustangs.com/forums/2011-mustang-gt-tech/541546-mt-82-transmission-additive-update-9-print.html

Post number 5 on the page above
My transmission has already had a complete rebuild but came out with exactly the same issues it went in with, as if nobody test drove the completed repair to verify it was fixed. Neither my service advisor nor service manager had ever heard of XL18 and apparently they cannot get it even if they wanted to, so I will guess that none was put in my transmission when it was rebuilt. Maybe it's included as a component of the new transmission fluid. I don't know.

As it is, I am on my own to solve the transmission issues. I have a faulty car and no practical way to get it fixed under warranty. My Boss was bone stock with about 5,000 kms on it when the transmission was rebuilt. The last time I talked with the service manager, they told me to drive it harder despite the crunching gears and if it breaks, they will fix it again. I would rather not experiment with fixes at my own great expense but I feel like I have a brand new, faulty car with no functional warranty.

I installed an MGW shifter to see if that would help but the shorter throw just makes the gears crunch faster. I will also pick up a Whiteline transmission bushing stiffener to see if that helps. If the XL18 works, it works. If not, it doesn't. It's not like I have a useful warranty to invalidate by trying.
 
So is this something we should be putting into our Trans? Or is it ALREADY in our trans fluid? I have the issue of not getting into 2nd gear very easily after start up, until a few miles are driven. Sounds like a typical issue, but would that help?
 
Boss0960 said:
My transmission has already had a complete rebuild but came out with exactly the same issues it went in with, as if nobody test drove the completed repair to verify it was fixed. Neither my service advisor nor service manager had ever heard of XL18 and apparently they cannot get it even if they wanted to, so I will guess that none was put in my transmission when it was rebuilt. Maybe it's included as a component of the new transmission fluid. I don't know.

As it is, I am on my own to solve the transmission issues. I have a faulty car and no practical way to get it fixed under warranty. My Boss was bone stock with about 5,000 kms on it when the transmission was rebuilt. The last time I talked with the service manager, they told me to drive it harder despite the crunching gears and if it breaks, they will fix it again. I would rather not experiment with fixes at my own great expense but I feel like I have a brand new, faulty car with no functional warranty.

I installed an MGW shifter to see if that would help but the shorter throw just makes the gears crunch faster. I will also pick up a Whiteline transmission bushing stiffener to see if that helps. If the XL18 works, it works. If not, it doesn't. It's not like I have a useful warranty to invalidate by trying.

I've got the same issues you have when the weather gets in around the 5 degree Celsius mark. Mine as well will be going in in spring time to get torn apart and see if they can figure out the issue as there is a heavy clunk going into 2nd, 3rd and 4th when transmission is not at operating temp. I have also changed to the MGW along with the McLeod High flow clutch line. This seems to have smoothed things out extremely nicely when at temp but really done nothing for cold temperatures. I am also on board to know if this XL18 is part of the new fluid or if it couldn't hurt to try adding to a 13 Boss.
 
Big shout out to (formerly) Tousley Ford. My XL18 is already here. I am impressed with such quick service. 8)

The only wrinkle in my plan is that we had some snow yesterday and they salted all the main roads. My Boss is in the garage for the foreseeable future. :'(
 

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