2018 New motor recommendations

[FordTechOne]

I’m not sure if the commentary is because you think I’m being argumentative - that is not my intention. my point is responding to the statement a non HO gen 2 will not work in an HO application. without any technical reasoning, I don’t see why this would be the case.

Nope, no issue. Just clarifying that a 2017-2020 Gen 2 3.5 non-HO cannot be used in place of a 3.5 HO due to the internal differences. A 2021 3.5 it not backward compatible per Ford, but the aftermarket may have already solved for that.

Again no intention to discredit you. Gen2 raptors are having crankshaft failures, it’s something I’ve seen on this forum a number of times and @GooseTuned has seen on some of his customer’s gen 2

Never seen a single stock one fail in my experience. On the modified trucks, has analysis been done to determine root cause? Forged cranks do not just break for no reason.

 

[full-race geoff]

As you might imagine, the crankshaft failures are catastrophic and it’s difficult to take anything conclusive away.

My speculation is I belive the harmonic balancers are failing and causing stress riser fractures to grow along the counterweights. In almost every high mileage raptor I’ve seen the crank pulley is shot



As best as I can tell, when a gen 3 crank is installed in the Gen 2 block there have been zero crankshaft failures. Of course none are being run with wonky harmonic balancers

 

[Zeusmotorworks]

@full-race geoff, Do we know when that “other” HB option will be coming to market?

 

[dillard09]

Nope, no issue. Just clarifying that a 2017-2020 Gen 2 3.5 non-HO cannot be used in place of a 3.5 HO due to the internal differences. A 2021 3.5 it not backward compatible per Ford, but the aftermarket may have already solved for that.

Never seen a single stock one fail in my experience. On the modified trucks, has analysis been done to determine root cause? Forged cranks do not just break for no reason.

He is what was left of mine in the oil pan. Just had an intake and a tune at the time. Let go at just over 100k. It is a 2017

 

[dillard09]

As you might imagine, the crankshaft failures are catastrophic and it’s difficult to take anything conclusive away.

My speculation is I belive the harmonic balancers are failing and causing stress riser fractures to grow along the counterweights. In almost every high mileage raptor I’ve seen the crank pulley is shot

View attachment 467190

As best as I can tell, when a gen 3 crank is installed in the Gen 2 block there have been zero crankshaft failures. Of course none are being run with wonky harmonic balancers

@full-race geoff I think you could be right. Here is a short video of what mine did. Drove it 1 mile after that and the crankshaft came apart and went through the oil pan. You can see the parts of it in my other post

 

[New recaros]

Just put this in there.

 

[NickW]

@full-race geoff, Do we know when that “other” HB option will be coming to market?

Am curious about this as well. If the HB are a potential root cause, I wonder how an ATI or Fluidampr balancer does?

 

[Old-Raptor-guy]

I’m not sure if the commentary is because you think I’m being argumentative - that is not my intention. my point is responding to the statement a non HO gen 2 will not work in an HO application. without any technical reasoning, I don’t see why this would be the case.


Again no intention to discredit you. Gen2 raptors are having crankshaft failures, it’s something I’ve seen on this forum a number of times and @GooseTuned has seen on some of his customer’s gen 2

I don't think you are being argumentative. An non-HO will bolt up to the truck and run, there is no doubt about that. I am just not sure why you would want to.

But alas the crankshaft issue.

I could be wrong, but having held a non-HO piston in my hand it appeared to be cast not forged where I believe besides the lower CR the HO piston is forged (could be wrong on that for sure). Have seen 7 or 8 non HOs with broken piston skirts in the last 2 years.

 

[full-race geoff]

HO pistons are cast, hyper-eutectic aluminum with a steel ring carrier. This is similar material and construction to non HO pistons. The difference is compression ratio and oiling ports