Symptoms
A tick-tick-tick on cold start that quiets as the engine warms, from a leak at the rear of a manifold. Quadratec says the rear manifold bolts on both the 3.8 and 3.6 are 'notorious for snapping'.
The fix, step by step
- Find the leak with the engine cold (a manifold that's black at the flange or a snapped bolt head is the giveaway).
- Penetrating oil the studs for a day or two.
- Unbolt the downpipe and remove the manifold.
- Extract broken bolts by drilling and using an extractor, or by welding a nut onto the stub.
- Chase the threads, fit new hardware and gaskets, torque to spec and reconnect the exhaust.
Tools & part numbers
- Penetrating oil
- sockets and extensions
- left-hand drill bits and extractors (or a welder)
- thread chaser
- torque wrench.
Where to buy the parts
OMIX 17451.24 exhaust manifold gasket set, 2012–18 JK 3.6Quadratec ↗Amazon ↗
Crown Automotive 68093232AA exhaust manifold gasket, 2012-on V6Quadratec ↗Amazon ↗
OMIX 17626.02 exhaust manifold, 2007–11 JK 3.8Quadratec ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Jeep Wrangler JK (2-door) parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.