NG 900/9-3 Idler Pulleys

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The serpentine belt, idler and tensioner pulleys should be inspected every service interval and in theory, replaced every 60k miles, but a pulley bearing often fails earlier. Cost of replacing two pulleys and the belt can be $200-300 for parts and labor plus towing. Alternatives include replacement as preventive maintenance (about $100 for a new belt and two pulleys), the short belt conversion ($60-70 for one pulley and the belt), and aluminum pulleys with replacable bearings. Repacking the pulley bearings is also possible to extend their life.

Belt and Pulleys

Short Belt

After the short belt conversion, using the Saab oem upper idler pulley, lower idler pulley bypassed, using Michel Briand's web site with instructions and pics: Short Belt Mod This is not a complete fix, because the remaining upper idler is still the one most likely to fail.

Short Belt

Aluminum Pulley

Short belt with aluminum pulley, oversized by about 10 mm. First version required machining to make it fit. An exact fit is now available, with a standard size 2603 replaceable bearing from Wazee Pulleys

Short Belt

Aluminum Idler - Closeup

74-mm diameter x 25 mm wide 2603 bearing, 40-mm OD, 17-mm ID Bearing insert, 17-mm OD, 10-mm ID Steel washer, about 15-mm OD Bolt, M8x125, Saab stock

Aluminum Idler

Short Belt Length

The normally recommended 97-inch "short" belt is a little long on my car, the line indicating correct tensioner arm position is just outside the limit marks. A slightly shorter belt like the Goodyear Gatorback 96.75" (2455mm) is a better fit.

Tensioner Arm Position

OEM Upper Idler

Grooved upper idler pulley, plastic, Saab 64-mm diameter x 24-mm wide Bearing, 44-mm OD, 8-mm bore Bolt, M8x125, 13-mm head, 35-mm length, w. 5-mm lead and floating washer

Upper Idler

Lower Idler

Smooth lower idler pulley, plastic, Dayco 80-mm diameter x 24-mm wide 2603 bearing, 40-mm OD, 17-mm bore Bolt, M8x125, 13-mm head, 25-mm length w. two retaining washers used to center bolt (sold as a kit)

Lower Idler

Tensioner Pulley

Smooth tensioner pulley, metal, Saab 90-mm diameter x 24-mm wide 2603 bearing, 40-mm OD, 17-mm bore Bolt, 22-mm head, 8-mm shaft, T40, 22-mm long w. one retaining washer, sold as a kit. New replacement kit shown on the left.

Tensioner Pulley

Bearing Repacking

Repack bearings by prying off the cover with a small pick or nail. Apply synthetic grease and rotate the bearing until the grease works itself through the race. Reapply the cover and then use silicone sealant to keep the grease from exiting when the pulley spins.

Part Numbers

  • Long (stock) Belt
    • Saab # 4904728 -
    • Dayco # 5061038 (103.25 inches) - AdvanceAuto
  • Short Belt
    • Dayco # 5060970 (~97 inches) - AdvanceAuto
    • Goodyear # 4060967 (96.75) - AdvanceAuto
  • Upper Idler
    • Saab # 4356127, plasic pulley -
      • Saab # 7978216, hex bolt - Saab Dealer
    • Aluminum pulley -
  • Lower Idler Kit
    • Saab # 4960290 (torx bolt & washer, 94-mid/97) -
    • Saab # 4752960 (hex bolt, 2 washers, mid/97-98) -
  • Tensioner Kit
    • Saab # 5172184 (w. washer and bolt) -