Plate hangs up

An NHTSA Engineering Analysis into Lear Siegler vehicles. Closed 12 July 1990.

Investigation
EA87013
Type
Engineering Analysis
Opened
16 March 1987
Closed
12 July 1990

What NHTSA investigated

Summary of information from manufacturer:anchorlok's investigation doesnot show that this product is defective in any sense.first, any hang upif it occurs at all, is very infrequent.second, even if it occurs, due tothe self-healing effect brought about by the chipping away of the conereceptacle and/or the tipping of the pressure plate, it has only a minimaleffect on loss of stroke.moreover, we have not found that the hang uphas a detrimental effect on vehicle braking performance, whether in aparked, emergency or decelerating condition....analysis:data indicates that the alleged problem may be caused by animproperly formed compression spring which allows the male portion of thepressure plate to contact the top peripheral of the female cone, possiblyrestricting the full function of the slack adjuster and pushrod.status:analyzing rockwell response of 11/6/87 and GM response OF9/3/87.AWAITING etf test results requested by odi memo dated 4/22/87.RYDER sytems reports an automotive car trailer sustained a hung up chamberon 29 september 87, resulting in the trailer and eight cadillac allantesbeing destroyed by fire.as a result of this development, ryder systems isconducting an investigation into the hang up phenomena.an ir is beingsent.===

Vehicles covered

MakeModelModel years
Lear SieglerLEAR SIEGLER1978–1987

Source

From NHTSA’s investigation file, rebuilt daily. To report a problem with your own vehicle, go to nhtsa.gov/report-a-safety-problem. All open investigations.