Name: Dorman - First Stop Brake Master Cylinder Jeep 1977-1978
Brand: Dorman
SKU: M39809
Price: 130.11 USD
Availability: InStock

// WHY THIS PART EARNS ITS SPOT

Master Cylinder Material: Cast Iron

Number of Outlets: 2

Mounting Hardware Included: No

Master Cylinder Bore Diameter: 1.063

Reservoir Included: Yes

Rearward Outlet Size: 1/2-20

Secondary Outlet Thread Diameter: 9/16-18

Package Contents: Master Cylinder

Sensor Included: No

// THE FULL RUNDOWN

Precise replacement - cylinder housing is constructed to match the casting material of the original part and ensure similar performance Durable design - all rubber components are made of high-quality EPDM compound for resistance to glycol-based brake fluid 100% new - made entirely of new materials, not remanufactured, to ensure highest quality and safety Strict specifications - made to meet rigorous SAE International standards This brake master cylinder is precision-engineered to match the design, function, and performance of the original master cylinder on specific vehicle years, makes and models. It is made of new, high-quality materials for a safe, durable replacement. Features: Notes: Other Part Numbers: Dorman #NBM39809 Proposition 65 ⚠ WARNING: Cancer and Reproductive Harm https://www.P65Warnings.ca.gov

// WILL IT FIT? THE STRAIGHT ANSWER

VEHICLE	YEARS	TRIM
Jeep CJ5	1977-1978	Base
Jeep CJ5	1977-1978	Renegade
Jeep CJ5	1977-1978	Golden Eagle
Jeep CJ7	1977-1978	Base
Jeep CJ7	1977-1978	Golden Eagle
Jeep CJ7	1977-1978	Renegade

JAP FITMENT PROMISE // If we confirm fitment for your rig and it doesn't fit, return shipping is on us. No restocking fee. That's the deal.

// GETTING IT TO YOUR GARAGE

THIS PART //

Ships UPS/FedEx ground — estimated $24.95. Additional ground items in the same order ship at reduced rates. Exact rate calculated at checkout.

REAL-COST SHIPPING

We charge what the carrier charges — no padding, no games. Ground parcels via UPS/FedEx, signature required. You see the exact number before you pay.

1-2 DAY HANDLING

Most in-stock parts leave the warehouse within 1-2 business days. Built-to-order parts show extended lead times.

LTL FREIGHT FOR THE BIG STUFF

Bumpers, hardtops, axles and full kits ship LTL truck freight (typically $400-500 per unit, plus shipping protection). Freight is charged per unit — two bumpers means two freight charges. Inspect before signing and note any damage on the delivery receipt.

30-DAY RETURNS

Unused, uninstalled parts in original packaging within 30 days. RMA required — start with a quick message. Shipping charges are non-refundable; freight returns quote at carrier rates.

FULL SHIPPING & RETURNS POLICY

// PAY YOUR WAY

CHECKING PAYMENT NETWORK…

ALL MAJOR CARDS + WALLETS

Visa, Mastercard, Amex, Discover, Apple Pay, Google Pay and Link one-tap checkout — live in our Stripe checkout right now. Card numbers never touch our servers.

BUY NOW, PAY LATER — LIVE

Klarna, Afterpay and Zip are active at checkout on eligible orders. Pick your split at payment — get the lift now, pay as you wheel. No JAP paperwork, approval happens right in checkout.

CRYPTO — LIVE AT CHECKOUT

Pay with crypto directly in our Stripe checkout — select the crypto option at payment and settle in USDC and supported coins. On-chain payment, standard order flow, same warranty.

3-D SECURE + RADAR ANTI-FRAUD

Every card payment runs Stripe Radar machine-learning fraud screening, with 3-D Secure (Visa Secure / Mastercard Identity Check) stepping in automatically when your bank requires it. Your card, verified by your bank.

PCI-DSS L1

HIGHEST CARD-SECURITY CERTIFICATION

AES-256 + TLS 1.3

ENCRYPTED IN TRANSIT & AT REST

TOKENIZED

WE NEVER SEE YOUR CARD NUMBER

Payments are processed by Stripe — the same infrastructure behind Amazon, Ford and Shopify checkouts. Dispute protection and receipt trails on every order. See our Privacy Policy.

// COVERED WHEN IT COUNTS

THIS PART //

Backed by the full Dorman manufacturer warranty. JAP is an authorized dealer — your warranty is valid from day one.

FULL MANUFACTURER WARRANTY

Every part ships new in the box with the manufacturer's standard warranty — terms and duration vary by brand (typically 1 year to limited lifetime on hard parts). We only sell through authorized channels, so coverage is never voided by gray-market sourcing.

WE RUN THE CLAIM WITH YOU

Warranty issue? Don't fight the manufacturer's phone tree alone. Hit our team with your order number and photos — we open the claim with the brand and stay on it until it's resolved.

WHAT WARRANTY DOESN'T COVER

Defects in materials and workmanship are covered. Trail damage, improper installation, modification, and normal wear items (bushings, pads, wear plates) generally are not — that's standard across every brand we carry.

SEPARATE FROM RETURNS

Warranty claims (defects after use) and returns (unused parts within 30 days) are different lanes. Not sure which applies? Message us first — we'll route it the fast way.

START A WARRANTY CLAIM

FITMENT	Jeep - See Description
BRAND	Dorman — shop all Dorman parts →
PART #	M39809
SKU	M39809
CATEGORY	OEM Parts > Brake > Master Cylinder Braces
AVAILABILITY	IN STOCK
RETURNS	30-day return window

Dorman - First Stop Brake Master Cylinder Jeep 1977-1978