F250 Pickup Brake Caliper Service Bulletin (85819)
Heater Core Case: All Technical Service Bulletins
Heater - Plenum Wind Whistle
Article No. 85-8-19
HEATER - PLENUM WIND WHISTLE VEHICLES WITH HEATER ONLY SYSTEMS
LIGHT TRUCK 1985 F-SERIES/BRONCO
The subject vehicles may experience an objectionable whistle and/or air leak, which may be noticed at highway speeds during no blower operation and
the functional control lever set in the off position.
A seam between the two halves of the heater plenum may separate slightly, leaking air and causing a whistling condition.
Figure 28 - Heater Plenum Chamber Air Leak and Wind Whistle Location - F-Series/Bronco
Verify that the whistle is originating from between the two plenum halves. If the source of the whistle is confirmed to be at the plenum, seal the leak with
hot melt glue, plastic weld, or caulking cord sealer. Refer to Figure 28 for the plenum leak and whistle location.
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP18471A85
TIME:
0.3 Hr.
DLR. CODING: Basic Part No. 18471 - Code: 27
Figure 28
