Product Questions?
Find quick answers about part fitment, availability, shipping, and ordering to help you buy with confidence.
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Additional Info: Shipping | Returns & Refund | Warranty
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Caterpillar® | 6.25"/D353/D379/D398/D399
High quality gaskets are crucial for ensuring a reliable seal between engine components and should be replaced regularly to prevent leaks and maintain optimal performance. These high-quality sets ship complete with all the necessary gaskets for your rebuild or repair and are backed by our comprehensive warranty.
Engineered for reliability, these replacement parts are compatible with 6.25"/D353/D379/D398/D399 applications. This series of engines covers a wide range of uses from construction to marine to mining, and more. The durable design and ease of maintenance has made this family of high displacement engines popular across the world.
Product Image Notice: For representation purposes only. Component colors or exact packaging layouts may vary while maintaining identical OEM fitment.
|
Part Number |
MCB399131GC (Gasket Kit - Major Overhaul) |
|---|---|
|
Vendor |
Interstate-McBee® (Aftermarket) |
|
Condition |
New |
|
OEM Brand Fitment |
Caterpillar® |
|
Engine Model |
6.25"/D353/D379/D398/D399 |
|
Length (in) |
50.0 |
|---|---|
|
Width (in) |
17.5 |
|
Height (in) |
3.5 |
|
Weight (lb) |
14.71 |
|
Notes |
Dimensions shown are for shipping and packaging purposes only. Actual product dimensions may vary. |
|
Processing Time |
1–3 Business Days |
|---|---|
|
Shipping Transit Time |
1–5 Business Days |
|
Total Estimated Delivery |
2–8 Business Days |
|
Shipping Policy |
Click Here |
|
Warranty |
2 Year |
|---|---|
|
Warranty Policy |
Click Here |
| Part # | Description | Qty |
|---|---|---|
| M-9F4446 | O-Ring Seal | 4 |
| M-0L1034 | Gasket | 2 |
| M-6L8037 | Gasket | 1 |
| M-6L8966 | Gasket | 1 |
| M-7L4302 | Gasket | 2 |
| M-7L4303 | Gasket | 2 |
| M-7L6005 | Gasket | 5 |
| M-7L8682 | Gasket | 1 |
| M-8L4156 | Gasket | 1 |
| M-8L4296 | Carburetor Gasket | 2 |
| M-8L5197 | Gasket | 1 |
| M-4L8120 | Oil Cooler Gasket | 1 |
| M-8L6207 | Gasket | 1 |
| M-8L8586 | Seal | 2 |
| M-8L9757 | Gasket | 2 |
| M-2M2489 | Oil Seal | 1 |
| M-4M8303 | O-Ring Seal | 2 |
| M-5M7877 | Torque Retainer Con Lock | 1 |
| M-8M8509 | Lock Nut | 1 |
| M-8M8997 | O-Ring Seal | 1 |
| M-9M1367 | Bolt Lock | 8 |
| M-9M4218 | O-Ring Seal | 2 |
| M-4L8121 | Gasket | 2 |
| M-9M6292 | Lock | 1 |
| M-9M6293 | Lock | 1 |
| M-9M9545 | O-Ring Seal | 2 |
| M-2N568 | Gasket | 2 |
| M-2N570 | Regulator Housing Gasket | 2 |
| M-2N741 | Gasket | 1 |
| M-2N2416 | Gasket | 1 |
| M-2N3553 | Seal | 10 |
| M-3N962 | Gasket | 1 |
| M-3N7731 | Gasket | 1 |
| M-4L8606 | Oil Cooler Lines Gasket | 3 |
| M-3N8654 | Gasket | 1 |
| M-2P8763 | Gasket | 1 |
| M-3P653 | Starter Seal | 2 |
| M-3P654 | Oil Tube Seal | 2 |
| M-3P656 | Oil Lines Seal | 4 |
| M-3P1155 | O-Ring Seal | 1 |
| M-3P1156 | Oil Lines Seal | 1 |
| M-1S7527 | Gasket | 2 |
| M-2S4750 | Access Cover Gasket | 1 |
| M-3S1427 | O-Ring Seal | 2 |
| M-5L3377 | Gasket | 2 |
| M-3S1889 | Water Lines Group Gasket | 1 |
| M-3S5849 | Gasket | 2 |
| M-3S6552 | Gasket | 1 |
| M-4S8513 | Gasket | 1 |
| M-9S4671 | Oil Seal | 1 |
| M-0T329 | Lock Nut | 16 |
| M-9H6067 | O-Ring Seal | 4 |
| M-4L8337 | Air Compressor O-Ring Seal | 2 |
| M-8L9757 | Gasket | 2 |
| M-7M7273 | Turbocharger Gasket | 2 |
| M-7L2013 | Gasket | 1 |
| M-1S4810 | Turbocharger Oil Supply Gasket | 2 |
| M-1S6595 | Turbocharger Oil Supply Gasket | 2 |
| M-2N1587 | Gasket | 1 |
| M-4L3437 | Access Cover Gasket | 4 |
| M-5L4949 | Lock Nut | 1 |
| M-4M8974 | Lock Nut | 1 |
| M-7M4353 | Gasket | 2 |
| M-8F8682 | Screw Lock | 3 |
| M-3P656 | Oil Lines Seal | 1 |
| M-8F8683 | Screw Lock | 1 |
| M-8M4438 | Power Train O-Ring Seal | 2 |
| M-4K1388 | O-Ring Seal | 3 |
| M-7L7735 | Gasket | 1 |
| M-5B8932 | Gasket | 1 |
| M-7F7669 | Gasket | 1 |
| M-4L6216 | Gasket | 1 |
| M-4L8120 | Oil Cooler Gasket | 2 |
| M-5L2093 | Gasket | 1 |
| M-8F4994 | O-Ring Seal | 16 |
| M-4H2494 | Sleeve | 8 |
| M-5H7704 | O-Ring Seal | 2 |
| M-4L8097 | Gasket | 16 |
| M-4L8337 | Air Compressor O-Ring Seal | 2 |
| M-6L4497 | Gasket | 8 |
| MCB7B2420 | Ferrule & Seal Assembly | 48 |
| MCB6B6224 | Ferrule & Seal Assembly | 64 |
| M-6L7816 | O-Ring Seal | 16 |
| M-6L7817 | O-Ring Seal | 32 |
| M-2N3236 | Exhaust Manifold Gasket | 16 |
| M-2N3597 | Rubber Seal | 8 |
| M-2N3583 | Housing Cover Gasket | 1 |
| M-3P647 | O-Ring Seal | 8 |
| M-1S4810 | Turbocharger Oil Supply Gasket | 2 |
| M-1S6595 | Turbocharger Oil Supply Gasket | 2 |
| M-6L5303 | Gasket | 2 |
| M-5H7704 | O-Ring Seal | 2 |
| M-5B3265 | Hard Washer | 2 |
| M-7F7510 | Lock Nut | 5 |
| M-1H8278 | O-Ring Seal | 2 |
| M-7K1978 | Seal | 2 |
| M-4L5832 | Gasket | 2 |
| M-2N3584 | Housing Cover Gasket | 1 |
| M-4L8121 | Gasket | 1 |
| M-4L9965 | Gasket | 2 |
| M-6L1649 | O-Ring Seal | 2 |
| M-2N2560 | Seal | 2 |
| M-2N8866 | Seal | 2 |
| M-3S1889 | Water Lines Group Gasket | 1 |
| M-3S3535 | Seal | 2 |
| M-8J6775 | Thread Seal | 8 |
| M-8M2331 | Gasket | 1 |
| M-6N9313 | Water Pump Seal | 2 |
| M-2H2665 | Elbow Seal | 8 |
| M-3P648 | O-Ring Seal | 2 |
| M-7C9710 | Gasket | 2 |
| M-6L5298 | Gasket | 1 |
| M-3N1372 | Seal | 2 |
| M-8L8227 | Seal | 2 |
| M-4H5952 | Gasket | 16 |
| MCB3N3220 | Cylinder Head Gasket | 8 |
| M-8N7780 | Shield | 16 |
| M-3P649 | O-Ring Seal | 4 |
| M-3P650 | O-Ring Seal | 5 |
| M-3P651 | Oil Cooler Lines Seal | 3 |
| M-3P653 | Starter Seal | 1 |
| M-3P655 | Oil Lines Seal | 2 |
| M-3P656 | Oil Lines Seal | 2 |
| M-3P658 | O-Ring Seal | 3 |
| M-0T329 | Lock Nut | 8 |
| M-2M9780 | O-Ring Seal | 1 |
| M-4L7904 | Gasket | 2 |
| M-7M6843 | Gasket | 1 |
| M-7M6844 | Gasket | 1 |
| M-8N452 | Gasket | 1 |
| M-2A3278 | Gasket | 2 |
| M-5H6012 | Lip Type Seal | 1 |
| M-4L3375 | Access Cover Gasket | 2 |
| M-4L3392 | Access Cover Gasket | 1 |
| M-4L3759 | Lock Nut | 6 |
| M-4L6182 | Lock Nut | 2 |
| M-4L6183 | Lock Nut | 4 |
| M-6L6487 | Gasket | 4 |
| M-4L6184 | Lock Nut | 1 |
| M-4L7586 | Gasket | 1 |
| M-4L8176 | Gasket | 2 |
| M-4L8767 | Lock Nut | 1 |
| M-5L2093 | Gasket | 1 |
| M-6L2069 | Gasket | 1 |
| M-9M1367 | Bolt Lock | 1 |
| M-5B5689 | Gasket | 1 |
| M-5N4687 | Gasket | 2 |
| M-5N4688 | Gasket | 2 |
| M-6L6489 | Gasket | 5 |
| M-0L1124 | Drain Plug Gasket | 1 |
| M-4L6706 | Gasket | 20 |
| M-4L7885 | Gasket | 4 |
| M-9M4217 | O-Ring Seal | 4 |
| M-3N1238 | Gasket | 2 |
| M-5P4941 | Seal | 2 |
| M-3S9643 | Thermostat Seal | 4 |
| M-3P1796 | Seal | 2 |
| M-1F3131 | Gasket | 3 |
| M-1F4419 | Gasket | 8 |
| M-2N5693 | Gasket | 2 |
| M-1F9223 | Cylinder Block Side C Gasket | 8 |
| M-4L3437 | Access Cover Gasket | 4 |
| M-4L8175 | Gasket | 1 |
| M-7L2905 | Gasket | 1 |
| M-7L3111 | Gasket | 3 |
| M-8L5457 | Gasket | 1 |
| M-5N3275 | Gasket | 1 |
| M-5L5840 | Washer | 4 |
| M-2A3278 | Gasket | 2 |
| M-2A4462 | Bell Housing Lock | 2 |
| M-4F7387 | Oil Cooler O-Ring Seal | 2 |
| M-2A5328 | Lock | 3 |
| M-2B5721 | Gasket | 1 |
| M-7B9514 | Lock | 2 |
| M-1F6936 | Gasket | 2 |
| M-2F4159 | Lock | 1 |
| M-3F4550 | Lock | 16 |
| M-3F4995 | Gasket - Air Compressor | 1 |
| M-7F2836 | Auxiliary Pump Lock | 3 |
| M-7F7510 | Lock Nut | 6 |
| M-9F4522 | Gasket | 1 |
| M-8F2534 | Gasket | 1 |
| M-1H8720 | O-Ring Seal | 1 |
| M-3H3451 | Lock Nut | 2 |
| M-6H4209 | Lock Screw | 8 |
| M-8H9180 | Lip Type Seal | 1 |
| M-7K1978 | Seal | 2 |
| M-0L364 | Lock | 1 |
| M-0L1213 | Gasket | 2 |
| M-0L1477 | Screw Lock | 2 |
| M-2L4730 | Gasket | 1 |
| M-2L5970 | Sleeve | 1 |
| M-3H2388 | O-Ring Seal | 1 |
| M-4L7631 | Gasket | 1 |
| M-4L7823 | Lock | 2 |
| M-4L7854 | Lock | 1 |
| M-4L7890 | Gasket | 8 |
| M-4L8191 | Gasket | 1 |
| M-6L1576 | Washer | 16 |
| M-6L1881 | Lock Nut | 24 |
| M-6L3636 | Gasket | 1 |
| M-6L5270 | Gasket | 2 |
| M-6L6580 | Gasket | 8 |
| CG73PR | Product Box | 1 |
Disclaimer: Limitless Contracting LLC is an independent supplier of premium aftermarket replacement engine parts. All manufacturer names, numbers, symbols, and descriptions (including Caterpillar, Cummins, Detroit Diesel, etc.) are registered trademarks of their respective owners. Their use on this website is strictly for identification and cross-reference compatibility purposes only. Limitless Contracting LLC is not affiliated with, endorsed by, or sponsored by any OEM trademark holders.

Online checkout is processed through Shopify's secure checkout and the payment providers enabled for this store. Checkout pages use SSL encryption to help protect personal and payment information during transmission.
For order assistance or part verification, contact our team before placing the order.
$3,153.02
Find quick answers about part fitment, availability, shipping, and ordering to help you buy with confidence.
We strongly recommend providing your Engine Serial Number (ESN) or VIN before placing an order. Diesel engine components can vary by engine model, CPL, and production year — even when part numbers look similar.
At Limitless Contracting, we verify compatibility whenever an ESN or VIN is provided to help ensure you receive the correct part the first time.
To avoid delays or incorrect orders:
Our goal is to eliminate guesswork and keep your equipment running with minimal downtime.
Limitless Contracting offers a structured return policy designed specifically for diesel engine components and heavy-duty parts.
Eligible items may be returned within 30 days of the invoice date, provided they are:
Certain items such as electrical components, gaskets, open kits, special-order items, and installed parts are non-returnable.
Approved returns are subject to a 15% restocking fee, and shipping charges are non-refundable.
For full details — including core returns, freight claims, refund timelines, and international return guidelines — please review our complete:
All returns require prior authorization. Unauthorized returns will not be accepted.
Online checkout is handled through Shopify's secure checkout and the payment providers enabled for this store. Checkout pages use SSL encryption to help protect personal and payment information during transmission.
Limitless Contracting does not ask customers to send full credit card numbers by email, text, or chat. If you prefer help before ordering, contact us and we can assist with part verification and order questions.
Yes. Most engine parts sold by Limitless Contracting are backed by warranty coverage under our Limited Warranty Policy.
Warranty coverage varies by product category and may include:
Warranty terms apply to defects in material and workmanship under normal use and service.
Please note:
Because diesel engine components operate under demanding conditions, warranty eligibility depends on proper installation, maintenance, and diagnostic verification.
For complete details — including exclusions, claim procedures, labor reimbursement limits, and manufacturer-backed components — please review our full:
All warranty claims require prior authorization. Core return labels must not be used for warranty claims.
Limitless Contracting LLC specializes in supplying aftermarket engine components designed to offer reliable fitment and operational durability.
We do not market our parts as original equipment. Instead, we source components through established distributor and supplier networks that focus on recognized aftermarket manufacturing and inspection standards.
Our sourcing partners focus on quality control tracking, including:
Parts in our catalog are offered as aftermarket replacement components for corresponding reference numbers, with fitment details provided to help customers verify compatibility before ordering.
We begin processing orders quickly to minimize downtime for our customers. If you need to change or cancel your order, please contact us as soon as possible.
Order Changes or Cancellations May Be Possible If:
Once an order has shipped, it cannot be canceled. In such cases, the order may fall under our standard return policy, including applicable restocking fees and return shipping costs.
Please note:
If you need assistance, contact our team immediately with your order number so we can review the status and advise on available options.
Free shipping may be available on select products or qualifying orders once a minimum order value is met. When applicable, this will typically be indicated on the product page or in promotional notices throughout the website.
If you have any questions regarding shipping eligibility, please feel free to contact our team.
We strive to keep our pricing fair, competitive, and transparent. While we do our best to offer strong value, we are happy to review reasonable price-match requests when possible. Please note that this typically excludes pricing errors, limited-time promotions, liquidation sales, auction listings, or pricing from membership-based marketplaces. If you believe you have found a comparable offer, we encourage you to reach out and our team will gladly review it.
Limitless Contracting LLC is headquartered in the greater Atlanta area in Lawrenceville, Georgia, USA.
Orders may ship from our inventory, supplier warehouses, or distribution partners depending on product availability and destination to ensure efficient and reliable delivery.
Most orders are processed and shipped within 1–2 business days, depending on product availability and order requirements. Our team works to process and dispatch orders as efficiently as possible; however, fulfillment time may vary based on factors such as order volume, product availability, and any special handling, assembly, or packaging requirements. Orders placed after business hours, on weekends, or on holidays will be processed on the next available business day.
For expedited shipping, the selected shipping service determines the delivery speed once the order has shipped. Please note that selecting expedited shipping does not guarantee immediate shipment, as order processing may still depend on product availability and preparation requirements. If your order is time-sensitive, we recommend contacting our team prior to placing the order so we can assist.
Once shipped, typical transit times are as follows:
Please note that transit times are estimates and may vary depending on carrier schedules, weather conditions, and destination accessibility. If you have questions regarding product availability, shipping timelines, or delivery options, our team will be happy to assist.
Once your order ships, you will receive a shipping confirmation email containing your tracking number and carrier information.
You can use this tracking number to monitor your shipment directly through the carrier’s website.
Tracking details are typically provided:
For freight (LTL) shipments, tracking may include:
If you created an account during checkout, you may also log in to view your order status and shipment details.
If you have not received tracking information or need assistance locating your shipment, please contact our team with your order number and we will be happy to assist.
Yes, we can support international shipping on a quote-based, case-by-case basis. Sourcing and shipping options depend on part availability, destination regulations, freight requirements, and carrier limitations.
Depending on the order size and destination, shipping options may include:
Transit timeframes, carrier availability, and shipping costs vary based on destination, package size, and weight. For an international shipping quote or to check destination eligibility, please contact our team with your part numbers and delivery address before ordering.
No. Limitless Contracting does not ship orders via the U.S. Postal Service.
Due to the size, weight, and value of diesel engine components, we ship exclusively through reputable national carriers and freight providers, including parcel carriers and LTL freight services.
This allows us to ensure:
Carrier selection is based on package size, destination, and delivery requirements.
If you have a preferred carrier or freight forwarder, please contact us prior to placing your order and we will review available options.
Yes. Our team is available to assist with orders and product inquiries. Customers may place orders directly through our website, by email, or by phone, depending on what is most convenient.
If you need help selecting the correct part, confirming availability, or discussing an order, you are welcome to contact our team and we will be happy to assist.
You can reach us by:
Our regular business hours are Monday through Friday, 8:00 AM to 6:00 PM (EST). Messages submitted outside of business hours will be reviewed and responded to on the next business day.
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Legal Disclaimer
All parts featured on this e-store are aftermarket replacement engine parts. All manufacturer names, numbers, symbols, videos, and descriptions are registered trademarks and/or copyrighted works of their respective owners. Limitless Contracting LLC makes no claim of ownership to these marks or videos, and their use is strictly for identification and informational purposes. This page may contain linked or embedded videos from external content creators. These videos remain the intellectual property of their respective creators and trademark holders. Any views, opinions, or statements expressed in such videos are solely those of the original creators and do not necessarily reflect the views or positions of Limitless Contracting LLC. Limitless Contracting LLC is not affiliated with, endorsed by, or sponsored by any of the trademark holders referenced herein.