9/23/2008
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Figure 1
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Figure 2
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New TTY Cylinder Head Bolt Kit and Torque Procedures for 88-95 Ford 5.0L Engines
In 1992, the type of cylinder head bolts used on the 5.0L engines was changed to Torque-To-Yield bolts (TTY). Depending on the build date of the engine, the 1992 model year engines came with either TTY bolts or standard torque, not a combination of the two. In 1993, TTY bolts were used on all 5.0L engines.
The two types of bolts that are used are physically different as you can see in Figure 1. The standard torque bolt is a non-flanged hex head bolt. The torque to yield bolt is a flanged head bolt. Both types of bolts may be used on any of the 5.0L engines. The bolts must all be the same style on each cylinder head.
Caution: Do not use both types of cylinder head bolts on one cylinder head. Do not mix and match. Each cylinder head must have all of one type of retaining bolt: Standard Torque or Torque-To-Yield.
The TTY cylinder head bolts will be available only in a packaged kit (F3ZZ-6065-E). The kit contains the following:
• (5) 7/16-14x3.94 bolts
• (5) 7/16-14x2.49 bolts
• (1) 3/8-16x7/16-3.93 stud
• (1) Instruction sheet (I.S. #6605)
Some applications use various quantities of studs for fastening items to the cylinder heads.
Torque Specifications
For the non-flanged standard hex head bolts, tighten in two (2) steps as follows:
1)Tighten all bolts in sequence (Figure 2) to 55-65 ft.lbs (75-88 Nm).
2) Tighten all bolts in sequence (Figure 2) to 65-72 ft.lbs (88-98 Nm).
For all Torque-To-Yield hex head bolts, tighten in three (3) steps as follows:
1) Tighten all bolts in sequence (Figure 2) to 25-35 ft.lbs (34-47 Nm).
2) Tighten all bolts in sequence (Figure 2) to 45-55 ft.lbs (61-75 Nm).
3) Tighten all bolts in sequence (Figure 2) an additional 1/4 turn (85-95 degrees).
Note: When the cylinder head bolts have been tightened following these procedures, it is not necessary to retighten the bolts after extended operation. TTY bolts must be replaced with new bolts. Do not reuse TTY bolts. TTY bolts may only be used one time.
Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.
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