The Merchant Automotive Injector and Return Line Seal Kit includes every seal needed to reinstall 4 injectors, one bank, on a 2001 - 2004 LB7 6.6 Liter Duramax Silverado or Sierra 2500HD/3500HD. It combines our LB7 Injector Seal Kit (copper washers, injector O-rings and injector body seals) with our LB7 Injector Return Line Seal Kit (return line seals and banjo seal). These seals should be replaced any time an injector or return line comes out.

Reused seals can let fuel leak under the valve covers, and on the LB7 that fuel can end up in the engine oil.

Key Features

• Seals 4 injectors: one bank of the engine
• Injector copper washers, O-rings and body seals
• Large injector return line seals plus the small return line banjo seal
• Viton O-rings and body seals
• 2 kits required per engine

Benefits

• Every injector and return line seal for one bank in one package
• Prevents fuel leaks under the valve cover after injector service
• Helps keep fuel out of the engine oil

Frequently Asked Questions

How many kits do I need?

Two. Each kit seals 4 injectors (one bank), so replacing all 8 injectors takes 2 kits.

Can I reuse my old injector seals?

No. The copper washers crush when the injector is torqued, and the O-rings and return line seals harden with heat. Reused seals are a common cause of fuel leaks and fuel in the oil on the LB7.

Why does fuel in the oil matter?

A leaking injector or return line seal under the valve cover lets diesel drain into the crankcase, which thins the oil and can damage the engine. New seals with every injector job prevent it.

Does this kit include the return line bolts?

No. If the factory return line bolts are rounded or damaged, see our Heavy Duty Injector Return Line Bolt, which has nearly double the tool engagement of the stock bolt.

Fitment

• 2001 - 2004 Chevrolet Silverado 2500HD / 3500HD 6.6 Liter Duramax LB7
• 2001 - 2004 GMC Sierra 2500HD / 3500HD 6.6 Liter Duramax LB7

Pulling injectors? See our LB7 Fuel Injector Removal Tool Kit and LB7 Injector Cup Puller. Resealing the valve covers?

Add the LB7 Lower Valve Cover Gasket, Lower Valve Cover Grommet 24 Pack and Upper and Lower Valve Cover Bolt Kit. Need extra banjo seals? See the Return Line Small Banjo Seal 3 Pack.

What's Included

• (4) Injector copper washers (GM 98486346)
• (4) Injector O-rings, Viton
• (4) Injector body seals, Viton
• (4) Large injector return line seals
• (1) Injector return line small banjo seal

For warranty information or to submit a claim, see our Warranty Form.

Details:

• Engine Manufacturer: Duramax
• Liter: 6.6 Liter
• Engine Designation: LB7
• Engine Years: 2001-2004

Applications:

• 2001-2004 Silverado/Sierra 2500HD/3500HD LB7