[modern] 4.0 Litre Rough Gear-Change

Recent comment has been on shift roughness on XJ40s.

My recently purchased 1993-1/2 Sovereign 4.0 litre has had a rough 3rd to
4th gear change, that the local dealers suggested was typical and nothing to
worry about.

A little research found a Jaguar Australia Service Newsletter No 27/95 dated
May 1995, SRO 44-91-12 which describes a problem of “Slip/Judder When
Reversing. Harsh 3-4 Upshift”

This problem potentially affects all 4.0 litre XJ6 and Sovereign, and 4.0
litre XJS up to 1995 MY with Transmission Serial Number up to # 158813, and
entails 1.05 hour Labor, and a $1 spring replacement.

The final result after this Service Modification is a transmission shift
quality as smooth as you had always expected.

This Jaguar Australia Service Newsletter is based on a UK Newsletter (number
not known) and presumably there is a Jaguar Cars North America equivalent.

The modification replaces the spring in the pressure reducing valve.

Roger Payne
GPO Box 39