Electrical Wiper Arm Stripped 07 Convertible

[Misneachail]

Hi All,
I desperately need help with a wiper issue. My drivers side wiper is stripped of the splines. Dealer wants 110.00 plus labor to install a new one. I found replacements for both drivers and passengers for $32 each, but when I got them, they came without splines in the connection. The company says this style "makes it's own" once it's installed. All the auto parts places don't carry the arms and have never heard of arms coming without splines. My mechanic says she's never heard of arms coming without splines & won't be liable for any damages during installation.

I've looked at tons of youtube videos, ebay listings, dozens of websites, junk yards and I'm having a very hard time trying to find wiper arms at all that fit and I'm getting pretty frustrated at the conflicting information I've been getting. Do I risk damage and install the non-splined ones on the advice of Late Model Restoration?
Is this normal for replacement parts for Ford? Help, please!

 

[MustangIIMatt]

Non-splined wiper arms that make their own as they're drawn onto the wiper arm shaft are very common these days. I see them primarily on the rear wipers of vans and SUVs, but there are front wiper applications as well.

That said, I've never replaced a wiper arm on an S197. LRS is a pretty trustworthy source though, they're all of 40 miles from me, so I've done business with them a lot and they've never steered me wrong.

 

[Misneachail]

Thank you so much for your reply!
This must not be super well known in my area. There's not a lot of mustangs around especially with the winters we get here (SE Idaho). She's my first mustang & I'm learning as I go. Conflicting information is so frustrating.

Do they just press on, or do you need a rubber mallet to tap it on? My daughter is going to be helping me. She spent 2 years as an ASE certified tech for a auto dealership before becoming a sheriff's deputy.

 

[MustangIIMatt]

Thank you so much for your reply!
This must not be super well known in my area. There's not a lot of mustangs around especially with the winters we get here (SE Idaho). She's my first mustang & I'm learning as I go. Conflicting information is so frustrating.

Do they just press on, or do you need a rubber mallet to tap it on? My daughter is going to be helping me. She spent 2 years as an ASE certified tech for a auto dealership before becoming a sheriff's deputy.

You line the arm up where it needs to be on the shaft, put the nut on the threads of the shaft, and tighten the nut, it'll pull the arm down over the shaft as you tighten it. When the nut bottoms out, you're good.

 

[Misneachail]

Oh my gosh, you rock! We can totally do that.