Description
Casting #2771239 & #2771231 Hydro-Boost | 1988-1991 Chevy & GMC C/K 2500/3500
SKU: BP7328
Bexar Pro Components Grade
In Stock & Ready to Ship
In Stock & Ready to Ship
“Engineered to restore maximum stopping power for GMT400 diesel and heavy-duty gas platforms, ensuring commercial-grade performance.”
Bring high-pressure braking assist back to your fleet with the **Bexar Pro Hydro-Boost**. Specifically engineered for the **1988-1991 Chevrolet & GMC 2500 and 3500 series trucks**, this unit provides the superior line pressure required for heavy-duty towing and vocational cycles. This hydraulic assist unit is a precision match for systems featuring **Casting #2771239** and **#2771231**. Each unit is reverse-engineered to identify and correct original design weaknesses, utilizing 100% O.E. quality seals to ensure your vehicle maintains maximum clamping force in demanding conditions.
Verified Casting Numbers
- 2771239
- 2771231
| Specification | Detail |
|---|---|
| Bore Diameter | 2.16-inch bore size |
| Booster Type | Hydraulic (Power Steering Powered) |
| Housing Material | Rugged Cast Iron |
| Stud Thread Size | 10 x 1.25mm |
| Components | 100% O.E. Quality Seals & Check Valves |
🛠️ Expert Installation & Shop Note
Based on our shop experience specializing in heavy-duty brakes since 1985:
- Pushrod Alignment: Precision alignment of the pushrod is critical for GMT400 hydro-boost units. Even a slight offset during installation can lead to internal cup over-extension—the leading cause of immediate leaks.
- Hydraulic Flush: These units share a reservoir with the power steering pump. We strongly recommend a total system flush with fresh fluid; contaminated oil is the primary cause of internal valve sticking and seal failure.
- Accumulator Check: If you experience a loss of assist after the engine is turned off, the nitrogen charge in the accumulator is likely depleted. Our units are bench-tested to ensure fail-safe performance and proper backup assist.
Availability & Fulfillment
In stock and ready for immediate professional fulfillment from our Kirby, Texas facility. Standard shipping typically departs within 24 hours of order confirmation.



