Some 2000-2006 Tundra pickups may emit an irritating squeal from the front of the engine during a cold start.
Toyota says the noise is most apparent during the first start-up in the morning and is likely due to the accessory drive belt slipping on the pulleys. Installing an upgraded automatic belt tensioner (part #16620-0W100) along with a new-design a/c compressor mounting bracket (part #88431-0C012) should prevent further noise issues.
Begin the fix by removing the lower engine cover and draining the cooling system. Next, remove the intake duct and the fan shroud, followed by the drive belt, fan, fluid coupling and fan pulley. Then remove the power steering pump and position aside, leaving the lines connected.
Continue the upgrade by removing the idler pulley and the right-and-left-side timing covers. Leaving the refrigerant lines attached, remove the a/c compressor from the old mounting bracket. Then remove the mounting bracket and discard.
Install the new-design a/c compressor mounting bracket along with the three attaching bolts. While pushing the bracket forward, hand-tighten bolts 1 and 2. Continue holding the mounting bracket forward, then tighten all three attaching bolts to 35 ft-lbs. in the following order: bolt 2, bolt 1 and bolt 3. This will help to properly align the bracket.
Now reinstall the a/c compressor to the mounting bracket. Remove the old automatic belt tensioner and install the upgraded unit in its place. Torque the new tensioner's three fasteners to 12 ft-lbs. To complete the fix, put the front of the engine back together and refill the cooling system.
Drivers of 2003-2004 GX 470 SUVs with factory height control systems may come into your store with an illuminated or flashing check engine light. When they do, hook up your scan tool and immediately start checking for trouble codes.
If the only code you pull is C1735, Lexus said, chances are the exhaust solenoid valve in the height control compressor has been infiltrated with water.
An improved solenoid valve is now available to address the concern, but technicians will have to replace the entire height control compressor with an upgraded unit (part #48910-60020) to gain the benefits from the new valve. After performing the parts swap, clear the trouble code then make sure the height control system is functioning as designed.
Some 1998-2005 Ranger Super Cabs with automatic transmissions and 4WD may emit a thumping or clunking sound on light acceleration or while coming to a stop under braking.
According to Ford, the noise can be accompanied by a slight vibration and is most likely due to a sticking condition at the rear driveshaft slip yoke splines.
Coating the splines with a new type grease should put an end to the noise. Order part #F87Z-4K277-AA for steel driveshafts, or part #4L5Z-4K277-AA for aluminum driveshafts.
Drivers of 1996-2003 General Motors vehicles with 3.1- and 3.4-liter V6 engines may come into your store with a complaint of an oil and/or coolant leak from the upper portion of the engine.
According to GM, both leaks are most likely coming from the lower intake manifold gasket. A new-design intake gasket (part #89017279) is now available to address the leakage issues.
When reinstalling the manifold, clean up all the bolts with a wire brush and apply threadlocker sealant to the bottom four threads. To prevent further leakage, GM also recommends tightening the vertical manifold bolts before the diagonal bolts.
Some 2005-2006 Jeep Grand Cherokees and 2006 Commanders built prior to Dec. 1, 2005, may produce an annoying squeaking sound from the rear suspension when the truck is driven over rough or bumpy roads.
After careful analysis, Chrysler has determined that the noise is most likely the result of defects in the rear spring isolators. Replacing all four isolators with an updated design (part #52089341AE) should put an end to the noise in short order.
Some 2000 S2000 models can emit a strange buzzing sound when decelerating in second or third gear between 3000 and 4000 rpm.
Honda said the noise is caused by backlash between the transmission gears. Although the backlash is normal, the carmaker said, it's more pronounced on the S2000 because of where the gearbox is situated—directly underneath the seats.
Installing a new clutch disc (part #22200-PCX-005, H/C 6234132) should help reduce or eliminate the buzzing noise. The new disc features heavier, beefier springs in the hub to help drown out the effects of the gear backlash.
“Factory Fixes” is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected]