Steering - Rapping or Clanging Noise
Article No.96-7-19
03/25/96
^ STEERING - POWER - "RAPPING" OR "CLANGING" NOISE - POWER STEERING COOLER - 4.0L ENGINE - VEHICLES BUILT BEFORE 3/1/96
^ NOISE - "RAPPING" OR "CLANGING" - POWER STEERING COOLER - 4.0L ENGINE - VEHICLES BUILT BEFORE 3/1/96
LIGHT TRUCK:
1990-96 AEROSTAR
This TSB is being republished in its entirety to include 1996 model year vehicles built before 3/1/96.
ISSUE:
A "rapping" or "clanging" noise may be heard when the steering wheel is turned rapidly or when turning on a bumpy road surface. This noise is caused by a pressure spike which results in a "hydraulic clang" in the serpentine tube of the power steering cooler.
ACTION:
Use the following Diagnostic Procedure to determine if a new power steering cooler is required. The new power steering cooler is a finned tube design unit.
DIAGNOSTIC PROCEDURE
1. Connect the return lines together to bypass the cooler.
2. Check for the "rapping" or "clanging" noise.
3. If the noise is still present, use normal diagnostics outlined in the appropriate Aerostar Service Manual. If the noise is gone, install a new design power steering cooler.
COOLER INSTALLATION
1. Remove the grille, bumper fascia, transmission auxiliary cooler and existing serpentine tube power steering cooler and return lines. Refer to the appropriate Aerostar Service Manual for service details.
2. Make two (2) sets of new holes in the bumper for the power steering cooler inboard bracket and the two (2) transmission cooler brackets, Figure 1 (hole sets # 2 and # 3).
^ Templates for drilling the holes are featured in Figures 2 and 3.
^ The two (2) old sets of holes remaining can be left open.
^ The shorter U-nuts and bolts can then be used to bolt the cooler in place.
^ The newly made holes require the longer U-nuts (N623343-S2).
3. Mount the outboard power steering cooler to the existing holes next to the driver's side frame rail, Figure 1 (hole set # 1).
4. Mount the inboard brackets in the same set of mounting holes, Figure 1 (hole set # 2)
NOTE:
1990 AEROSTARS BUILT AFTER 5/31/90 ALREADY HAVE THE COOLER MOUNTING HOLES IN THE CORRECT POSITIONS FOR THE NEW POWER STEERING COOLER. THEREFORE, THE COOLER CAN BE BOLTED RIGHT IN WITH SHORT U-NUTS WITHOUT MAKING ANY MODIFICATIONS TO THE BUMPER.
5. Install new transmission cooler hoses.
a. Tighten the screw clamps to 2.8-4.0 N.m (25-35 lb-in).
b. Use the 400 mm hose to connect the top transmission cooler nipple to the inboard metal tube. Use the 340 mm hose to connect the bottom cooler nipple to the outboard tube.
c. Route the hoses so they do not kink.
6. After the cooler is bolted in place, install the new return lines using the new return line gear fitting (connector assembly).
7. Once the hoses are connected to the return lines, proceed as follows:
a. Secure the tie strap, that comes attached to the hoses, to the stabilizer bar. This prevents the hoses from rubbing against the A/C condenser.
b. Allow the hoses to hang in their natural position.
c. Secure the tie strap so that the hoses are not pulling on the cooler connections or the metal return lines.
8. Evacuate and fill the power steering system according to the procedure outlined in the appropriate Aerostar Service Manual.
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 95-18-8
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage For 1992-95 Model Year Vehicles, Basic Warranty Coverage For All Other Model Year Vehicles
OPERATION DESCRIPTION TIME
960719A Install New Cooler - 2.7 Hrs.
With A/C
960719B Install New Cooler - 1.9 Hrs.
Without A/C
DEALER CODING
CONDITION
BASIC PART NO. CODE
3D746 56
OASIS CODES: 303000, 702000, 702100