Originally Posted by cowmilker08

I didn't think you were supposed to use a standard grinding wheel on aluminum. Something about the Al collecting in the grittiness of the wheel until BOOM it explodes from the extra mass of the Al.

Originally Posted by cowmilker08

I didn't think you were supposed to use a standard grinding wheel on aluminum. Something about the Al collecting in the grittiness of the wheel until BOOM it explodes from the extra mass of the Al.

Originally Posted by deadsenator

I had the dreaded "chirp-chirp" from the front of the truck on the way home last week and limped into the driveway. I figured it was just a pulley, but after lots of reading, I found that the OBS tensioner is a high wear part and there is a TSB (98-23-14) for the newer and improved SD style dual-arm tensioner. Even though my tensioner still had some life left and it was indeed only the lower idler pulley that was trashed, I considered it prudent @140k miles to perform the update and be done with it. I would also need a new 122.7" belt.

I found lots of great info, but it was spread around, so I thought I'd try and collect some images of my job into one post. I've uploaded a few images of the task to an imgur album (including a copy of the TSB). Maybe I didn't find much because it is so darn easy and also many folks did the upgrade so long ago that links had expired.

Well, here's a fresh one:

truck tensioner images - Imgur

Descriptions of the upgrade and a copy of the TSB are in the album's images.

Here's also a video of it running:

Ford OBS 7.3 Powerstroke dual-armed tensioner upgrade running - YouTube

Parts used:
(Ford) F8TZ-6B209-BA Dual Tensioner (F-Series) Pickup
(Ford) F8TZ-8620-FB Belt (F-Series) Pickup (JK8-1227)


Since I can't think of everything, please tell me what I may have missed or just post your ideas on this mod.

Thanks everyone even though you didn't know you helped, just like I hope this will help someone else.

DS
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