Crown Victoria Front Springs - p71interceptor.com

Part Number
 Load Rate (Newton-Meters)
 Load (Newtons)
 Coil Diameter (mm)
Spring Code
 Tape Color
 Comments
 Price









D9AZ-5310-AN
 122.6
 11000
 19.65
 NUL
 N
 Blue
 Police
 $105.57









F4AZ-5310-A
 77.1
 9481
 17.3
 AFD
 2
 Yellow
 Civilian
 $63.45
F4AZ-5310-B
 77.1
 9943
 17.3
 BOS
 3
 Yellow
 Civilian
 $66.02
F4AZ-5310-C
 77.1
 10404
 17.3
 CKV
 4
 Yellow
 Civilian
 $81.87









F4AZ-5310-E
 98.1
 10266
 18.2
 ETR
 6
 White
 HPP
 $86.38
F4AZ-5310-F
 98.1
 10862
 18.2
 FPK
 7
 White
 HPP
 $97.73
F4AZ-5310-G
 98.1
 9670
 18.2
 DHL
 5
 White
 HPP
 $66.53









1W7Z-5310-AA


ALT
 A
??5??
 Red
 HPP (After 02/05/01)
 $40.05
1W7Z-5310-BA


AMT
 B
??6??
 Red
 HPP (After 02/05/01)
 $41.93
1W7Z-5310-CA


AET
 C
??7??
 Red
 HPP (After 02/05/01)
 $46.20









D9AZ-5310-R
 71.8
 9960
 17.60
 RIM
 R
Towncar $105.57
D9AZ-5310-S
 71.8
 10410
 17.60
 SAP
 S
Towncar Obsolete
F4AZ-5310-E
 98.1
 10266
 18.2
 ETR
 6
Towncar
Limo
 $86.38
F4AZ-5310-F
 98.1
 10862
 18.2
 FPK
 7
Towncar
Limo
 $97.73
F4MY-5310-A
 71.8
 9510
 17.1
 AML
 W
Towncar & Grand Marquis
 $105.57
F4MY-5310-B
 71.8
 9960
 17.1
 BRK
 X
Towncar & Grand Marquis Obsolete
F4MY-5310-C
 71.8
 9510
 17.1
 CSH
 Y
Towncar & Grand Marquis $105.57
F8VZ-5310-AA
 71.8
 9960
 17.1
 AOK

Towncar
 Superceded by F8VZ-5310-BA
F8VZ-5310-BA
 71.8
 10410
 17.1
 BRX
Green
 Towncar
 Superceded by F4AZ-5310-C

Notes:

Due to the lever action of the lower control arm, the spring rate at the wheel (wheel rate) is considerably lower than the spring rate at the spring mount in the control arm. (This is why most people can not noticeably compress a crown vic front spring when it's laying loose on the ground out of the car. But most will be able to push down on the front corner of their car and have it move noticeably downwards when the spring is mounted in between the lower control arm and the vehicles frame)

Understand the concepts of oversteer and understeer before altering springs rates. (On a street driven car, it is usually desirable to have a slightly higher wheel rate in the front than on the rear. This reduces the possibility of "spinning out".)

Crown vics typically have a slightly different load on the front left and front right tires. To attain equal ride height on the front left and front right corners, most crown vics will have different springs on each corner. For example, a 2001 HPP with ETR on one side and DHL on the other side. The rates of the DHL and ETR springs are the same, but the height of the ETR spring will be slightly higher under a given load than the DHL spring will. Note that all 1993-2002 police interceptors use NUL springs on both front corners, but these springs have a very high rate (700 lbs/in).

The part number for the rubber insulator that sits between the top of the spring and the vehicles frame is C9AZ-5415-B. Some people say to replace this part with a new service assembly every time the spring is changed to prevent undesirable noises and other complaints. Some say only to change it if it "looks bad". Additionally if this part repeatedly falls of the spring during installation, tape or an adhesive will likely make the job "go a lot easier".

The front spring replacement procedure listed in the factory shop manual for later model crown vics involves removing the bolts that retain the control arms to the vehicles frame. But if you live in the "rust belt" where salt is used to clear the roads during the winter of snow, these bolts will very likely be seized to the control arm bushings. Additionally, realigning the control arm with the frame so that the bolts can pass through the bushings is often a time consuming and frustrating process. Seperation of the lower balljoint from the knuckle can work instead. But the lower balljoint nut has been known to be stubborn. And use of a "pickle fork" will severly damage the joint even if the boot isn't torn. So if you seperate the lower balljoint from the knuckle, plan on installing a new balljoint before reassembling the front suspension.

Police springs are shorter than civilian springs when laying loose on the ground out of the car. But the vehicles static ride height with police springs installed will be slightly higher than with civilian springs installed. Additionally, a crown vic with police springs installed will be less likely to "bottom out" when driving over potholes, hills and other road imperfections due to the higher rate of the police springs. This helps prevent damage to undercarriage components such as oil pans, exhaust components, bumper covers, floor pans, etc.

Multiply Newton-Meters by 5.71 to obtain foot/pounds
Divide Newtons by 4.45 to obtain pounds

Wheel Studs
Front - 1/2 20 x 2 F1VY-1107-A
Front - 1/2 20 x 2 F5AZ-1107-AA
Front - 1/2 20 x 2 F0LY-1107-A
Front - 1/2 20 x 2.25 F8AZ-1107-AA

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