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how many 3.6 engine failures

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Rodeoflyer

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I agree, I have a buddy here in CO with a 2002 TJ 2 door with the 4cyl (2.5l) which is basically the same engine 1/2'd. It's a manual trans as well and he's been all over the state and UT with it. He's even rolled it on its side a few times.. they just tip it back onto it's wheels and carry on.
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How many Turbo 2.0 Slow Blow up ? Again, we have no access to that information but. I’m guessing many more than the naturally aspirated 3.6.
 

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A compete failure of the 3.6 is relatively rare, considering the number of them that are out there.

The two most common things I’ve seen are:
  • The plastic oil filter housing cracking. Easy fix.
  • A rocker failure due to a bad bearing. If caught early, it’s an easy fix. If not, it could lead to needing a new motor. I’ve seen a few posts from members on here that had this issue.
What symptoms to lookout for on the rocker failure? Or is it something that needs inspecting or preventative maintenance?
 

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Do NOT go cheap on quality oil, and DO NOT extend the oil life to maximum recommended, I always change between 4-6000 miles.
How is that defined given that every popular oil on the market meets API SN, SN+, or SP?
 

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How many Turbo 2.0 Slow Blow up ? Again, we have no access to that information but. I’m guessing many more than the naturally aspirated 3.6.
What are you basing that guess on? We certainly aren't seeing a lot of them "blow up" on here other than the few that had the coolant pump issue.
 

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The 3.6 is a great engine! I would not want any other engine that Wrangler offers as of current. I was thinking about the 392, then I found out about the cylinder deactivation.. No longer interested........ But everybody to their own.
 

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The 3.6 is a great engine! I would not want any other engine that Wrangler offers as of current. I was thinking about the 392, then I found out about the cylinder deactivation.. No longer interested........ But everybody to their own.
They're still doing that cylinder deactivation (MDS - Multi-Displacement System)?
I had that on my 2016 Ram 1500 Hemi 5.7L, and it was irritating as hell! (I bypassed it every time I got into the truck). Let me tell you first hand, a V8 running on four is NOT smooth.
 
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Yeah you can bypass MDS....its not that big a deal.
 

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They're still doing that cylinder deactivation (MDS - Multi-Displacement System)?
I had that on my 2016 Ram 1500 Hemi 5.7L, and it was irritating as hell! (I bypassed it every time I got into the truck). Let me tell you first hand, a V8 running on four is NOT smooth.
At least you are able to deactivate it, the VCM on the Honda is terrible. Every time you touch the accelerator it makes a pronounced "bump" when it engages the full complement of cylinders. They have this fluid filled motor mount to dampen the "bump" but so often it goes bad, luckily ours hasn't yet as it is a pain to change out. I'd love to see what the real world fuel savings of an MDS/VCM system is, I bet it is under 1 MPG.
 

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At least you are able to deactivate it, the VCM on the Honda is terrible. Every time you touch the accelerator it makes a pronounced "bump" when it engages the full complement of cylinders. They have this fluid filled motor mount to dampen the "bump" but so often it goes bad, luckily ours hasn't yet as it is a pain to change out. I'd love to see what the real world fuel savings of an MDS/VCM system is, I bet it is under 1 MPG.
I deleted my Silverado’s DoD system and lost about 5 mpg. Seen several others that average 10-12mpg after deleting. It’s an effective way of saving fuel, for sure. It’s just obnoxious and introduces mechanical failure points that otherwise wouldn’t be there.
 
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I deleted my Silverado’s DoD system and lost about 5 mpg. Seen several others that average 10-12mpg after deleting. It’s an effective way of saving fuel, for sure. It’s just obnoxious and introduces mechanical failure points that otherwise wouldn’t be there.
Sure it does.. if you 'deactivate' something that should be working/constantly mechanically lubed and broken in/worked it causes failures.

If if wasn't ever there to begin with we wouldn't have failures. Ford is notorious for this..VVT sucks. However it saves fuel and less emissions.

FCA is getting there.. I'm now looking at that new GM 2.7 turbo in the CO trucks.

I'm sure the manufacturers don't want you using VVT or disabling it as well hence the new turbos across the board. I'm on board.. let's TURBO! I'll take a turbo hybrid over full electric every day of the week.
 

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It’s too bad FCA didn’t modernize the 3.8. Solid 30+ years of history of high mileage engines. Solid enough to run a Supercharger or Turbo for hundreds of thousands of miles with no issue. My 08 had 321,000 when I traded in and it still ran quiet and smooth. The biggest issue with the 3.8 was running 5w20 oil in a motor specked to run 10w30 (oil consumption in some). There were about 1M JK with the 3.8 produced before they switched to the 3.6. And people who never check their own oil would kill an engine quick. Yes we have had quite a few in the family and all were very high mileage, no oil burners.
The downside of the 3.8 in the JK was never the engine but the transmissions. Both the 4spd auto and 6spd manual were too highly geared (for fuel economy).
For comparison a 3.8 auto would need 4.88 gears just to match a factory Rubicon 3.6 auto with 4.10 final gear. I can tell you from experience a 3.8 with a RIPP Supercharger ( 240whp/260ftlbs torque at the wheels) and geared properly will easily outdo the 3.6 or 2.0Turbo and still last longer. The bottom end torque with the old school pushrod engines is right up there.
 
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That might be the best answer... was the 3.8 insults engine or trans. I've owned the worst 4/5/6 speed trans in dodge/fca history the 45/6/65/66RFE.. however it took 10k to build it bulletproof.
 
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