Dayco Automatic Belt Tensioner Jaguar S Type X XF XJ6 XJ8 XK XK8 XKR Land Rover

Dayco No Slack Automatic Belt Tensioner

Designed to maintain constant tension on serpentine belt drives
Serpentine belt drives consist of a single belt that powers most, if not all, of the engine’s accessories.

To maintain the proper tension throughout the drive, an automatic, spring-loaded tensioner is incorporated into the drive system geometry.

Dayco’s Automatic Belt Tensioner features a patented “flat spring” design that’s engineered to provide less operating range variations in tension.

This reduces the risk of premature accessory bearing failure due to high tension when a new belt is installed.

It also lessens the risk of belt squeal and slippage, or poor accessory performance caused by low tension after the belt begins to stretch and wear. A Teflon strip wound within the spring resists abrasion.

The flat spring itself is coated to resist rust.

Other superior design features include a steel locator pin (where the application demands).

A heavy-duty cast aluminium spring case resists cracking and fatigue. The heavy-duty cast aluminium arm offers additional strength and less distortion.

An aluminium retainer ring locks the spring case and arm together, and seals against corrosion.

A steel pivot tube (where the application demands) provides additional strength for critical torque requirements.

A thermoplastic rubber “spring slot plug” keeps out harmful contaminants. The lubricated nylon “pivot tube bushing” and “spring bushing” promote quieter performance.

A rubber “O” ring seals against dust and grime.

The zinc coated mounting bolt resists rust, and is concentric for a more even degree of constant tension.

In order to meet OEM performance standards, Dayco Automatic Tensioners come with either a glass-filled polymer (plastic) or steel pulley, that features a dust cover to protect against contaminants.

Fits the following Make, Model, Series:

Jaguar > S Type > Mar 1999 - Jul 2002, 4.0L, V8, 32V, DOHC, MPFI, EngCode: AJ28

Jaguar > S Type > Mar 1999 - Dec 2002, 3.0L, V6, 24V, DOHC, MPFI, EngCode: AJ30

Jaguar > S Type > Jul 2002 - Sep 2004, 2.5L, V6, 24V, DOHC, MPFI, EngCode: AJ25

Jaguar > S Type > Jul 2002 - Jan 2008, 4.2L, V8, 32V, DOHC, SCMPFI, Supercharged, EngCode: AJ

Jaguar > S Type > Jul 2002 - May 2008, 4.2L, V8, 32V, DOHC, MPFI, EngCode: AJ

Jaguar > S Type > Jan 2003 - Dec 2004, 3.0L, V6, 24V, DOHC, MPFI, EngCode: AJ30

Jaguar > X Type > Sep 2001 - Feb 2005, 2.5L, V6, 24V, DOHC, MPFI, EngCode: AJ25

Jaguar > X Type > Sep 2001 - , 3.0L, V6, 24V, DOHC, MPFI, EngCode: AJ30

Jaguar > X Type > May 2002 - , 2.0L, V6, 24V, DOHC, MPFI, X400, 117kW, EngCode: AJ20

Jaguar > XF > Jun 2008 - Jul 2009, 4.2L, V8, 32V, DOHC, SCMPFI, Supercharged X250, 306kW, EngCode: AJ34

Jaguar > XF > Jun 2008 - Jul 2009, 4.2L, V8, 32V, DOHC, MPFI, X250, 219kW, EngCode: AJ34

Jaguar > XJ6 > Mar 2004 - Jun 2008, 3.0L, V6, 24V, DOHC VVT, MPFI, 179kW, EngCode: AJ30

Jaguar > XJ8 > Jul 2003 - Apr 2009, 3.5L, V8, 32V, DOHC, MPFI, XJ350, EngCode: AJ

Jaguar > XJ8 > Jul 2003 - , 4.2L, V8, 32V, DOHC, MPFI, XJ350, EngCode: AJ34

Jaguar > XJ8 > Jul 2003 - , 4.2L, V8, 32V, DOHC, SCMPFI, XJ350, EngCode: AJF

Jaguar > XK > Jul 2006 - Dec 2009, 4.2L, V8, 32V, V-DOHC, MPFI, EngCode: AJ

Jaguar > XK8 > 2002 - 2008, 4.2L, V8, 32V, DOHC VVT, MPFI, X150, EngCode: AJ34S, Supercharged

Jaguar > XK8 > Oct 2002 - Jun 2006, 4.2L, V8, 32V, DOHC VVT, MPFI, X100, 224kW, EngCode: AJ34

Jaguar > XKR > Oct 2002 - Dec 2009, 4.2L, V8, 32V, V-DOHC, SCMPFI, X100, 298kW, EngCode: AJ34, Supercharged

Land Rover > Discovery > Apr 2005 - Sep 2009, 4.4L, V8, 32V, DOHC, MPFI, Discovery 3, EngCode: 448PN Jaguar V8

Land Rover > Range Rover > Aug 2005 - Sep 2009, 4.2L, V8, 32V, DOHC, SCMPFI, 291kW, EngCode: 428PS, Supercharged

Range Rover > Sport > Aug 2005 - Sep 2009, 4.2L, V8, 32V, DOHC, SCMPFI, 287kW, EngCode: 428PS, Supercharged