How To Replace An Idler Arm
On a recent inspection on the front end I noticed that my idler arm had some slop in it. I also had some wandering on the road… and this is a typical symptom of a bad idler arm. Along with:
- play back and forth in the steering wheel while sitting still… this may also be other loose suspension components… so check them all over.
- with the truck properly supported and the front wheels off the ground, it's possible to move either wheel side to side without any steering wheel movement…. as talked about above.
I replaced this arm in about 30 minutes. Granted I am a professional, so expect no more than an hour.
It’s a relatively painless and simple process. If you can change a flat tire or change brake pads, you’ll be fine. An alignment check is recommended when finished with the idler arm replacement.
- jack and jack stands
- measuring tape to determine which arm in truck 2.5 inch between holes or 3.5 inch <<< IMPORTANT!!!
- idler arm, I got Moog part number K8739T
- pickle fork
- hammer or mini sledge hammer
- 21 mm 1/2 inch drive shallow socket
- 1/2 inch driver breaker bar or ratchet and pipe
- 1/2 inch drive torque wrench (ft lbs - up to 150 ft lbs) reversible torque wrench can substitute for breaker car/ratchet and pipe)
- locktite (blue)
- dykes or side cutters or needle nose pliers for cotter key removal and install
Idler Arm Replacement
First, lift and support vehicle on passenger side using the jack & jack stands.
Next, remove the cotter key (pin) from idler arm lower nut, and remove lower nut. Place pickle fork between idler arm joint and tie rod, strike to seperate. It's the area to the right on this photo. If you need to see a "before" picture, scroll down and see what it looks like after installtion:
Remove the two bolts holding the arm to the frame (shown on the upper left area of the above photo), then remove arm. Be sure to put locktite or threadlocker on the bolts going in to frame when you put them back.
Install arm basically reversing the steps for removal. Torque bolts to frame accordingly (instructions with torque specs included) - install arm joint into tie rod...torque and install cotter key. Here is a photo of the new one, installed:
Don’t forget your grease fittings and greasing the new arm. Enjoy your new idler arm!
This article and associated photos were written and contributed by thefordmaniac, and is used with permission.
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This tech article was originally posted at FordF150.net. It is primarily intended for Ford trucks but most likely also applies to other Ford models.