Long Tube Header (Banks / Borla / Hedman)
Replaces the cast manifold and downpipe with equal-length primaries merging into a single collector. Best top-end gain available for the 4.0L, but expensive and a common cracking point.
The factory cast manifold is the single biggest exhaust restriction on the 4.0L and is notorious for cracking (especially the rear runner) due to thermal expansion against a fixed bolt pattern. A long-tube header solves both problems — better scavenging via tuned-length primaries, and ductile mild steel or stainless that flexes without cracking.
The Banks Torque Tube was the gold standard for a decade and is still respected, claiming ~17 hp / 25 lb-ft on a stock 4.0L. Borla, JBA, and Hedman all make long-tubes; pacesetter is the budget option. Pacesetter and Hedman tend to need re-flanging or have fitment quirks. JBA shorty headers (see next entry) are an more manageable fit but give up some of the long-tube gain.
Real dyno data suggests stock 4.0L gain of 8-15 whp / 10-15 lb-ft with a long-tube and matching cat-back, weighted toward the top end. Strokers see proportionally more because the engine actually wants the airflow.
Common issues: O2 sensor bung placement, EGR tube fitment on pre-95 trucks, header bolts backing out (use studs and copper nuts), and fitment with motor mount lift. Check your specific year — Renix (87-90), pre-OBDII HO (91-95), and OBDII (96+) all have different sensor and EGR requirements.
Why it works
- best exhaust gain
- won't crack like cast manifold
- tuned scavenging
Trade-offs
- expensive
- labor-intensive
- fitment quirks
- EGR/O2 complications
Tools required
- socket set
- torque wrench
- penetrating oil
- O2 sensor socket
- EGR tube flare wrench
Parts
| Part | Vendor | Est. price |
|---|---|---|
| Banks Torque Tube header | Banks Power | ~$850 |
| Borla long-tube header | Borla | ~$750 |
| Hedman Hedders | Hedman | ~$380 |
| Header stud kit | ARP | ~$60 |
Sources
Related
- Shorty Header (JBA, Pacesetter)
- Cat-back Exhaust (Banks Monster / Magnaflow / Dynomax)
- All Jeep Cherokee XJ guides & tools
- Browse the full DIY database
Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.