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Fab Heavy Parts  |  SKU: FN26033184

Level Sensor 591-3427 535-6922 Fits for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655

€701,95

Our price doesn't include any taxes, duties or VAT.

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

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

Estimated delivery time 3-6 workdays

No Core Charge

We don't have a core charge for any products.

Frequently Asked Questions

Shipping and Delivery

What countries do you ship to?

We can ship to these countries:

Indonesia, Japan, Malaysia, Philippines, Singapore, South Korea, Thailand, Vietnam

United States

Belgium, San Marino, Italy, Spain, Netherlands, France, Germany, Finland, Austria, Denmark, Ireland, Luxembourg, Monaco, Norway, Sweden, Switzerland, Portugal, Poland, Hungary, Canada, Estonia, Australia, Mexico, New Zealand, Bulgaria, Croatia, Cyprus, Czechia, Greece, Greenland, Iceland, Liechtenstein, Lithuania, Malta, Romania, Russia, Slovakia, Slovenia, Latvia, Turkey, United Kingdom

How long will it take to receive my order?

Estimated delivery time to USA: 3-6 workdays;
Estimated delivery time to Canada, Mexico: 4-7 workdays;
Estimated delivery time to Australia: 4-7 workdays;
Estimated delivery time to European countries: 4-7 workdays;
Estimated delivery time to Asian countries: 3-5 workdays.

Returns and Refunds

How do I return a product?

Our return policy lasts 60 days. If 60 days have gone by since the delivery, unfortunately, we can’t offer you a refund or exchange.


To be eligible for a return, your item must be unused, not installed, clean and in the same condition that you received it. Shrink wrapping must not be broken. It must also be in the original packaging.


To complete your return, we require a receipt or proof of purchase.
Please do not send your purchase back to the manufacturer.



Steps of Returning Products to Fab Heavy Parts

1. Request returns in seconds at our return portal.

2. Fill in the email address you left with the order & the order number to start the return. Note: a correct order number format starts with a # hashtag

3. Select the items you wish to return and choose the return reason and upload photos of the received package.

Then, Fab Heavy Parts receives your return request and starts to process your return request. We may contact you for more details.

Steps after the approval of your return request:

1. A Return label will be sent to you via email. Print out the return label, place it on the parcel, and take it to the drop-off point. Make sure you properly pack the product for return if it’s returnable.
2. A refund of the original purchase price will be issued.
Any questions about returning products, please feel free to contact us at info@fabheavy.com

How long will it take to receive my refund?

Once your return is received and inspected, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund.If you are approved, then your refund will be processed, and a credit will automatically be applied to your credit card or original method of payment within 3-10 business days.

Payment Methods

What kind of payment methods do you accept?

We accept all major credit cards, PayPal, Google Pay, Apply Pay, Shop Pay, debit cards.

If you prefer offline payment, please contact us to get our bank transfer details.

Taxes or duties

Will I receive customs/import duties?

For orders shipping to the United States, our price includes the import fees. The receiver/buyer doesn't need to pay any extra customs taxes, or duties for their packages. For orders shipping to non-US countries, please check our policy here.

TESTIMONIALS

It was great ordering from you guys if we ever need anything else we sure will order from you guys.

I.H.

From the US

Great price and fit my 844 lull perfectly , along with fast shipping.

M.L.

From the US

very very good and I received it very quickly. thank you very much.

L.F.

From the EU

Removed old tank and install new, install pipes and fill with oil, no modifications at all. GREAT FIT !!!!!

R.P.

From the US.

Received everything as stated and so far very happy with the product. Will purchase again when more parts are needed.

E.S.

From the US

Ask a Question

Feel free to leave your question with us. Our current response time is around 24 hours, though we will get back to you faster when possible.

Level Sensor 591 - 3427 535 - 6922 Fits for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655 - Fab Heavy Parts
Fab Heavy Parts

Level Sensor 591-3427 535-6922 Fits for Caterpillar C4.4 C3.6 Engine D4 CS66B CS56B CS14 CS16 AP455 AP655

€701,95

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

Equipment Compatibility

Note: Compatibility is provided for reference. Please verify against your part number before ordering.

Fits the Following Applications:

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:

Package Contents

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.

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