Overview
The Rubicon Express RE4020 is a pair of extreme-duty adjustable front upper control arms for Jeep TJ, XJ and ZJ long arm suspensions. The product is sold as a pair, with driver and passenger side arms, and it allows pinion angle adjustment.
The arms are for long arm kits only and are not intended for short arm suspensions. The finish is gray powder coat.
Key features
- Adjustable front upper control arm
- Extreme-duty build
- Allows pinion angle adjustment
- Driver and passenger side arms
- Gray powder coat finish
- Long arm kits only
Long arm geometry and pinion angle
Long arm suspensions move the axle in a wider arc, so the upper arms carry more of the work in setting pinion angle. An adjustable upper arm lets you bring the pinion closer to the correct angle without changing the lower arms. Small changes at the upper arm shift the driveline, so adjust in small steps and check each change with an angle finder.
Upper arm bushings, ends and mounts are worth checking when the arms go in, since loose parts can undo a good setting. Pair the arms with a lower control arm setup and a driveline that suits the new angle. Recheck the alignment once the suspension has settled over the first few drives.
- Make small adjustments and measure after each change
- Inspect upper arm ends and mounting hardware
- Match the arms to the long arm kit in use
Specifications
| Brand | Rubicon Express |
|---|---|
| Part number | RE4020 |
| UPC | 614901441062 |
| Position | Front upper |
| Adjustment | Pinion angle |
| Finish | Gray powder coat |
| Suspension type | Long arm kits only |
| Sold as | Pair |
Vehicle fitment
These arms are for TJ, XJ and ZJ long arm suspensions, covering the Jeep Wrangler (TJ), Cherokee (XJ) and Grand Cherokee (ZJ).
Confirm fit for your vehicle’s year, model and trim before ordering, including any LJ or MJ application.
Installation notes
The arm allows pinion angle adjustment, so set and check the pinion angle after installation. Confirm the arm suits your long arm kit before you begin.
What’s included
A driver side and a passenger side front upper control arm, sold as a pair.
