https://jalopnik.com/jeep-wrangler-engine-explodes-after-owner-tows-vehicle-1846493328
A 2021 Jeep Wrangler’s 3.6-liter V6 engine apparently tried revving to eight times its redline after the owner left the vehicle’s transfer case in low-range while flat-towing, The Drive reports. The resulting stresses tore the engine apart, yielding a scene that looks as if it might have been caused by a grenade.
The car website spoke with the foreman of a north Florida shop to learn more about the ruined white 2021 Jeep Wrangler Unlimited Rubicon that had been flat-towed behind an RV. From The Drive:
Video of the mechanical disaster that once was a dual overhead cam, 3.6-liter, naturally aspirated V6, made it to TikTok and YouTube. Prepare your souls for destruction.
As you can see in the clip, the crankshaft is broken, the block and pan are in pieces, there’s no flywheel or clutch kit to be found, the catalytic converter is destroyed, the bell housing is toast, the manual transmission input shaft has been sheared, and — though it’s hard to tell — I’m fairly sure the passenger’s side upper control arm was bent by the flying debris. It’s just a huge mess.
But that’s what happens when you have lots of reciprocating mass moving far faster than it was ever designed to. The Pentastar Upgrade was really only ever meant to consistently rev to roughly 6,600 RPM. With the Rubicon coming stock with a 4.10:1 axle ratio and a 4:1 transfer case low range ratio, and with first gear at 5.13:1, the vehicle’s crawl ratio is 84.13:1. This means the engine spins 84.13 times as fast as the rear wheels do.
If we assume that the RV was towing this Jeep at 60 mph (we don’t really know how fast it was traveling; the shop foreman that The Drive spoke to guessed 55), we can use the fact that the Jeep’s stock 285/70R17 BF Goodrich KO2s are rated to turn 645 revolutions per mile to learn that, at that speed, the vehicle’s tires were spinning at 645 rpm.
The 84.13:1 crawl ratio tells us that, when in first gear and low range, the engine spins 84.13 times as fast as the wheels. This means that, with the RV towing the Jeep at 60 mph, the Jeep’s wheels were trying to force its engine to spin at 54,264 RPM. That’s 8.22 times the engine’s 6,600 RPM redline. No wonder it blew up (If I had to guess, it happened well before 50,000 RPM).
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Check the YouTube on the link above.
A 2021 Jeep Wrangler’s 3.6-liter V6 engine apparently tried revving to eight times its redline after the owner left the vehicle’s transfer case in low-range while flat-towing, The Drive reports. The resulting stresses tore the engine apart, yielding a scene that looks as if it might have been caused by a grenade.
The car website spoke with the foreman of a north Florida shop to learn more about the ruined white 2021 Jeep Wrangler Unlimited Rubicon that had been flat-towed behind an RV. From The Drive:
Video of the mechanical disaster that once was a dual overhead cam, 3.6-liter, naturally aspirated V6, made it to TikTok and YouTube. Prepare your souls for destruction.
As you can see in the clip, the crankshaft is broken, the block and pan are in pieces, there’s no flywheel or clutch kit to be found, the catalytic converter is destroyed, the bell housing is toast, the manual transmission input shaft has been sheared, and — though it’s hard to tell — I’m fairly sure the passenger’s side upper control arm was bent by the flying debris. It’s just a huge mess.
But that’s what happens when you have lots of reciprocating mass moving far faster than it was ever designed to. The Pentastar Upgrade was really only ever meant to consistently rev to roughly 6,600 RPM. With the Rubicon coming stock with a 4.10:1 axle ratio and a 4:1 transfer case low range ratio, and with first gear at 5.13:1, the vehicle’s crawl ratio is 84.13:1. This means the engine spins 84.13 times as fast as the rear wheels do.
If we assume that the RV was towing this Jeep at 60 mph (we don’t really know how fast it was traveling; the shop foreman that The Drive spoke to guessed 55), we can use the fact that the Jeep’s stock 285/70R17 BF Goodrich KO2s are rated to turn 645 revolutions per mile to learn that, at that speed, the vehicle’s tires were spinning at 645 rpm.
The 84.13:1 crawl ratio tells us that, when in first gear and low range, the engine spins 84.13 times as fast as the wheels. This means that, with the RV towing the Jeep at 60 mph, the Jeep’s wheels were trying to force its engine to spin at 54,264 RPM. That’s 8.22 times the engine’s 6,600 RPM redline. No wonder it blew up (If I had to guess, it happened well before 50,000 RPM).
------------------------------------------------------------------------
Check the YouTube on the link above.
