Level Sensor 591-3427 535-6922 Fits for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655
Level Sensor 591-3427 535-6922 Fits for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655 is backordered and will ship as soon as it is back in stock.
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Description
Description
Level Sensor 591-3427 535-6922 – Replacement for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655
Aftermarket diesel exhaust fluid (DEF) level sensor engineered for accurate fluid level monitoring and reliable emissions system performance in Caterpillar engine and equipment applications. Precision-manufactured components ensure drop-in compatibility with correct fitment.
Technical Specifications
- Part Numbers: 591-3427, 5913427, CA5913427, 535-6922, 5356922, CA5356922
- Tank Interface: 4
- Suction Fitting Diameter: 3/8 in
- Return Fitting Diameter: 5/16 in
- Coolant Inlet Fitting Diameter: 5/8 in
- Coolant Outlet Fitting Diameter: 5/8 in
- Header Height: 11.4 in
- Installation Depth: 337.41 mm (~13.28 in)
- Wire Length: 15.5 in
- Electrical Connector: Deutsch DT4 (STD), 4-pin
- Condition: New, aftermarket replacement
- Function: Monitors DEF tank fluid level and transmits data to the engine control module to maintain emissions compliance and prevent low-fluid shutdowns across Caterpillar Tier 4 engine and equipment applications
Equipment Compatibility
Note: Compatibility is provided for reference. Please verify against your part number before ordering.
Fits the Following Applications:
- Caterpillar Engine: C4.4, C3.6
- Caterpillar Tractor: D4
- Caterpillar Asphalt Paver: AP400, AP455, AP500, AP555, AP600, AP655, PE636
- Caterpillar Compactor: CP12, CP14, CP16, CP56B, CP68B, CP74B, CS12, CS13, CS14, CS16, CS17, CS19, CS56B, CS66B, CS68B, CS74B, CS76B, CS78B
- Caterpillar Motor Grader: 120 GC
Why Choose This Level Sensor
The DEF level sensor is a critical emissions system component in your Caterpillar Tier 4 engine — it continuously monitors fluid level in the DEF tank and feeds real-time data to the ECM to maintain SCR system operation and regulatory compliance. A failed or inaccurate level sensor triggers fault codes, activates warning indicators, and can result in derate conditions or equipment shutdown that halts production on active job sites. This replacement unit delivers:
- Accurate level monitoring – Engineered to meet the signal output, connector, and dimensional specifications of Caterpillar C4.4 and C3.6 DEF system requirements
- Exact-fit installation – Direct replacement with correct installation depth, fitting diameters, wire length, and Deutsch DT4 4-pin connector to match Caterpillar equipment specifications without modification
- Durable construction – Built to withstand continuous DEF exposure, thermal cycling, and the demanding duty requirements of Caterpillar paver, compactor, grader, and tractor applications
- Cost-effective solution – Aftermarket quality at a fraction of dealer pricing
Package Contents
- 1 × Level Sensor 591-3427
Essential for Caterpillar C4.4, C3.6 engine, D4 tractor, AP455, AP655 paver, CS66B, CS56B, CS14, CS16 compactor, and 120 GC motor grader DEF system maintenance and level sensor replacement. Keep your Caterpillar equipment delivering full emissions compliance and uninterrupted operation on every job.
1 Year Warranty
1 Year Warranty
Fab Heavy Parts is excited to offer a 12-month warranty on all new replacement/aftermarket parts starting from your original purchase date.
Enjoy peace of mind with Fab Heavy Parts!
For more warranty details, please check out our warranty policy.
Fast Delivery
Fast Delivery
Estimated delivery time 3-6 workdays
No Core Charge
No Core Charge
We don't have a core charge for any products.
Frequently Asked Questions
Do you ship to Australia?
Yes, we ship Australia-wide with tracked international freight. All orders are carefully packaged to ensure parts arrive safely.
How long does shipping to Australia take?
Typically 5–10 business days depending on your location and the freight method selected at checkout.
Will I need to pay import duties or GST?
Goods with a customs value of AUD 1,000 or less are exempt from customs duty. For orders over AUD $1,000, GST and import duties may apply at the Australian border — buyers are responsible for any applicable charges upon delivery.
Are your parts compatible with Australian-spec machines?
Yes, most of our parts are internationally compatible. Please check the fitment details on each product listing to confirm compatibility with your specific machine.
Can I return a part if it doesn't fit?
Yes, we accept returns within 60 days of delivery for unused parts in original condition. Please contact our team to initiate a return.
What payment methods do you accept?
How do I find out the shipping cost for my order?
Shipping costs are calculated based on your location and the size of your order. To get an accurate shipping quote: add the part(s) to your cart, then enter your country, state, and zip code in the shipping estimator at the cart page — the shipping cost will be calculated instantly.
