
Core Return
The return of an acceptable core must be sent back to RedLine Transmissions within twenty-one (21) days of receiving your transmission. Please make sure the transmission and torque converter are fully drained. If more time is needed, just ask! We would be happy to make arrangements to fit your schedule.
Items that need to be included with your core:
LIKE FOR LIKE Transmission Core
Torque Converter
RedLine Tote with all brackets and clips
Level on the side on the transmission
Fitting on the side of the transmission
Dust pan cover
Please contact our office at 330-345-3000 or email Rachel Mireiter to make arrangements and get your prepaid return label. Your core charge will be refunded when RedLine Diesel Power receives an acceptable core after it passes inspection. Your core refund may be forfeited if the transmission is not received within 30 days of delivery.
RESOURCES

Installation Instructions
Important Installation Instructions – Please Read Carefully
Please take a moment to thoroughly review the installation instructions provided, or forward them directly to your installer. These guidelines contain critical details specific to your performance transmission and must be followed exactly as written.
This is not a stock transmission—it's a high-performance unit built to handle more power and stress. Because of this, proper installation is absolutely essential to ensure reliable function and long-term durability.
If your installer has any questions or uncertainties at all, we encourage them to contact us directly before proceeding. We're here to help and want to ensure everything is done correctly the first time.
⚠️ Please note: Improper installation will result in the transmission not functioning as intended and will automatically void the warranty.

Warranty Registration Forms
Warranty Activation Requirements – Action Needed
To activate your warranty, this form must be fully completed and returned to us within 30 days of installation. If we do not receive the completed form within that timeframe, the warranty will be void.
We strongly recommend filling out the form during the installation process. Some of the required information is much easier to access while the transmission is being installed and may not be available afterward.
Please ensure all sections are filled out completely and accurately to protect your warranty coverage.
Warranty Coverage
Our transmissions include a limited warranty that covers defects in workmanship and materials under normal use.
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Coverage Period: Typically ranges from 12 to 24 months, depending on the transmission model and intended use (standard, towing, or high-performance). Refer to your specific build sheet for exact terms.
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What’s Covered: Internal parts, labor for internal repairs, and defects due to build quality or component failure under normal operating conditions.
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What’s Not Covered:
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Improper installation or setup
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Lack of proper fluid or incorrect fluid type
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Overheating due to insufficient cooling
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Tuning-related failures
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Abuse, racing, off-road use (unless specifically built for it), or neglect
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Failure to complete the break-in service and regular maintenance
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Labor for non-warrantable items
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Warranty Activation Requirements
To activate your warranty:
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The Warranty Registration Form must be fully completed and returned within 30 days of installation.
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All installation and setup procedures must follow our official instructions.
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Failure to submit this form on time or incomplete information will void your warranty.
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What to Expect form your new Build
Congratulations on your new performance transmission! This unit has been custom-built for strength, durability, and enhanced drivability. To help you get the best results and longest service life from your investment, please review the following information on how your transmission will perform and what’s required during the break-in and maintenance periods.
Performance & Feel
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Firm, Positive Shifts
This transmission is built for performance. You’ll notice a firmer, more deliberate shift feel compared to a stock unit. This is normal and intentional—it's a sign the upgraded internals and improved hydraulic control are working as designed. -
Stronger Torque Handling
Designed for increased horsepower and towing capabilities, your transmission is engineered to hold power with reduced slip and faster engagement.
Break-In Period – First 500 Miles
Proper break-in is critical to ensure long-term reliability and performance.
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Drive Conservatively: Avoid wide-open throttle and aggressive driving during the first 500 miles. This gives the clutches and bands time to seat properly. Do NOT exceed half throttle during this timeframe.
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Normal Shifting: During break-in, shifts may feel slightly more pronounced. This will smooth out as the transmission settles in.
Initial Service
We recommend a transmission service at 1 year or 20,000 miles,
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Use the Recommended Fluid Only!
Refer to your instruction sheet for the specific fluid type required. Using incorrect fluid can affect performance and void your warranty. -
Use OEM Filters ONLY!
Check out the links below for MORE details and get your know everything about your transmission.


2018 RAM 2500
68RFE Transmission - "The 550"
Solid Transmission Build!
"Have had a RedLine Transmission in my truck for 1,200 miles. Transmission is very solid and you can feel the transmission holding on to the gears longer while in use. Another big plus is that they had my truck in and out in five days. This is great because my truck is a daily driver and tow rig. 100% recommend this company. Can't wait to tow the fifth wheel this summer.
- Tim B.

2002 Dodge Ram 2000
47RE Transmission - "The 650"
Built & Shipped!
I purchased a built 47RE Transmission for my Ram pickup and it has been driving beautifully so far. Amazing customer service, great product and a pleasure to work with. Definitely recommend!
- Deagan O.

2016 Ram 2500
68RFE Transmission - "The 700"
Highly Recommended
"Had by 2016 68RFE rebuilt at RedLine. Nothing but good things to say. They are priced right. It's been 8 months and 10,000 miles and it is running super strong with no issues. Highly recommended!
- Aris A.

2020 RAM 2500
68RFE Transmission - "The 550"
Nothing but the best!
Quality of the work and the service you receive. Worth it to check them out and get your work done.
- Steve Z.


