Will a L86 fit in a 2020 GMC Sierra with a L87

[Kevin999]

I have a 2020 sierra with a bad engine (l87).

I happen to have an l86 laying in my garage that has low mileage. Is this replacement possible. Any help is greatly appreciated. 

[newdude]

15 minutes ago, Kevin999 said:

I have a 2020 sierra with a bad engine (l87).

I happen to have an l86 laying in my garage that has low mileage. Is this replacement possible. Any help is greatly appreciated. 

 

 

Nope. 

 

L86 uses different cylinder deactivation.  L86 has a VLOM (Valve Lifter OIl Manifold) and has AFM (only 4 cylinders deactivate).  L87 is a DFM setup (all 8 cylinders are active cylinders) and does NOT use a VLOM for their operation.  L87 has 8 individual solenoids to control the cylinder deactivation, therefore, L87 is wired up different from the L86.  

 

The front end accessories/pulleys are different as well.  L86 has an offset water pump, L87 has a center water pump so the hoses are plumbed differently.  

Edited September 17, 2023 by newdude

[CamGTP]

Wonder if just the block is the same. Could swap over all the top end parts and front end parts if they are.

[newdude]

10 hours ago, CamGTP said:

Wonder if just the block is the same. Could swap over all the top end parts and front end parts if they are.

 

 

No.  AFM (L86) vs DFM (L87).

 

L86.  Note the AFM oil passages in the valley.

 

 

 

L87 DFM.  Completely different valley casting and setup.

 

 

Edited September 22, 2023 by newdude

[Sam2008]

Hi Kevin if you don't use that L86 are you willing to sell it...