No spline in new rear wiper arm?

[waterskier_erie]

Hello All,

2005 4Runner SR5. 101k. Rear wiper only cleaned a small area of rear glass. Replaced wiper with aftermarket trico but condition wasn’t much better. Tried bending the trico to conform to glass. A little better. Finally, I took off the rear wiper arm head cap (cover that goes over wiper arm bolt) and found that the plastic arm was partly cracked.

Got an oem replacement arm (85241-35031) from ToyotaPartszone.com. I have the OEM 4Runner Manual and after removing the 10mm nut holding on the wiper arm and coaxing off the old arm, I then cleaned off the spline on the shaft. The illustration in the manual shows the wiper arm to have serrations/splines already formed in the female half which meshes with the wiper arm motor shaft. Oddly enough, the new arm part didn’t have any splines…it was just a smooth round hole.

I installed it anyway, thinking it’s designed to just make its own serrations when the nut is tightened?

Anyone else install their own and notice the lack of splines/serrations in a new part?

The wiper works fine so far. The shaft is tapered so if I further I tighten it, it will form deeper grooves.

Thanks for any help you can provide.

Ted

 

[Asmara]

Hello All,

2005 4Runner SR5. 101k. Rear wiper only cleaned a small area of rear glass. Replaced wiper with aftermarket trico but condition wasn’t much better. Tried bending the trico to conform to glass. A little better. Finally, I took off the rear wiper arm head cap (cover that goes over wiper arm bolt) and found that the plastic arm was partly cracked.

Got an oem replacement arm (85241-35031) from ToyotaPartszone.com. I have the OEM 4Runner Manual and after removing the 10mm nut holding on the wiper arm and coaxing off the old arm, I then cleaned off the spline on the shaft. The illustration in the manual shows the wiper arm to have serrations/splines already formed in the female half which meshes with the wiper arm motor shaft. Oddly enough, the new arm part didn’t have any splines…it was just a smooth round hole.

I installed it anyway, thinking it’s designed to just make its own serrations when the nut is tightened?

Anyone else install their own and notice the lack of splines/serrations in a new part?

The wiper works fine so far. The shaft is tapered so if I further I tighten it, it will form deeper grooves.

Thanks for any help you can provide.

Ted

This is correct. There are no splines. Puzzled me when I replaced mine too. I think the shop manual mentions it but it has been a few months since I replaced mine.

 

[waterskier_erie]

Thanks Asmara! When I did this last month, the 10mm nut came off with a little coaxing, but the old female part that has the spline was real tight, so very carefully cutting a groove part way through the sides at 12 and 6 o'clock positions with a dremel, while simultaneously avoiding cutting the rubber gromet, did the trick. I just put in a large screwdriver in the groove and twisted it to crack it apart and not damage the male side spline.

 

[Asmara]

Thanks Asmara! When I did this last month, the 10mm nut came off with a little coaxing, but the old female part that has the spline was real tight, so very carefully cutting a groove part way through the sides at 12 and 6 o'clock positions with a dremel, while simultaneously avoiding cutting the rubber gromet, did the trick. I just put in a large screwdriver in the groove and twisted it to crack it apart and not damage the male side spline.

I used a gear puller. It is a real pain to get the wiper off and you don't want to break off the mount in the door.

 

[Kstimp]

I replaced the wiper arm on my 03 the other day, and as I was tightening that 10mm nut forming the female spline the stud twisted off. Exactly as it happened I was thinking to myself "I wonder how I will know when I got it tight enough." The arm doesn't seem to want to come off and is functional, but if I wanted to fix it would I need to replace the whole motor assembly now? Seems like that stud should be heat treated or a larger diameter.