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HomeShop by DepartmentPerformanceTransmissionsTransmissionSuncoast Allison Cat 4 950 HP+ Trans with Converter 2017-2019 4WD

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Suncoast Allison Cat 4 950 HP+ Trans with Converter 2017-2019 4WD

Thoroughbred Sku #: SUNGMAX-CAT4-L5P-1719-4WD-CRE

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PAYMENT NOTE: If you choose Pay Core Later, from the Core option below, you will not be able to pay for this order using Affirm or PayPal

$10,750.00

+ $400.00 Shipping

* Core Exchange Option:

Terms & Conditions for Cores

Many stock replacement parts such as turbos, injectors, injection pumps, and high pressure oil pumps have a core charge that is associated with the new replacement part. You must return the old part to receive a refund on the core charge.

In some cases, the core is not reusable, such as in the event of a cracked case, at which point the core deposit would not be credited as the core component is not reusable.
Cores that have been disassembled and/or have missing and/or damaged major components will not receive full core credit.
Returned cores must be on a "like-for-like" basis, meaning that the returned core has the exact same fitment as the remanufactured component that was purchased. If the core is not "like-for-like," your core may not be eligible for return/credit.
You are responsible for core return shipping cost.

If you plan on returning your core you have two options.

Thoroughbred Diesel offers defer the upfront core charge when purchasing via credit card payment.

OPTION 1: You can accept the core charge, which means you will be charged for the part AND the core at time of purchase. You still have the option to send it back, and if you do, the core will be refunded back on the card used, presuming the core meets core criteria and the core is returned within 30 days from the time your order is received. If you return your core after 30 days you may refer to the Core Charge Timeline below as to how you will be refunded.

Core Charge Timeline

If the core is returned after 30 days, 90% of the core will be refunded.
If the core is returned after 60 days, 70% of the core will be refunded.
If the core is returned after 90 days, 50% of the core will be refunded.
After 6 months cores will be accepted at Thoroughbred’s discretion.

OPTION 2: You can defer the core charge. If you defer, you will not be charged for the core at the time of purchase. You will have 21 days from the time your order is received to send the core back. If the core is not received within the 21 days, your credit card will be charged for the core amount on your order. If you return your core after 21 days, you may refer to the Core Charge Timeline below as to how you will be refunded. When Core deferral (Pay Core Charge Later) is limited to payment by credit card only. ***When using PayPal or Affirm as your method of payment “Core Deferral (Pay Core Charge Later)” is not available. The core must be paid at time of purchase. ***

Core Charge Timeline

If the core is returned after 21 days, 90% of the core will be refunded.
If the core is returned after 60 days, 70% of the core will be refunded.
If the core is returned after 90 days, 50% of the core will be refunded.
After 6 months cores will be accepted at Thoroughbred’s discretion.

Core Return Procedure

Please keep all original packaging of your new item to be used for the core return.
Drain all fluids: oil, fuel, etc. out of the core before it is returned.
Place any plastic plugs or caps received on the new item back onto the core.
To insure UPS, Fed Ex, or USPS will not reject the package due to fuel or oil leakage, please wrap the core in a plastic garbage bag.
Place core inside the box.
If core return paperwork was inside the box, please complete the form and send back with the core.
Please provide a tracking number to [email protected]. Without a confirmed tracking number we cannot guarantee your core refund
If you have questions please call our core department 859-737-4966 ext. 5

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Product Details

Product Name: Allison Category 4 950 HP+ Transmission
Manufacturer: Suncoast
Manufacturer Part #: GMAX-CAT4-L5P
Thoroughbred Diesel Part #: SUNGMAX-CAT4-L5P
Fitment Notes: 2017-2019 4WD GM Duramax L5P

The Flexplate

This SunCoast Allison billet SFI certified billet flexplate replaces the factory flex plate with an improved billet steel one piece design. This eliminates the weak factory flex plate. This replacement Allsion flex plate is a must with the high torque in conjunction with a better designed torque converter that can transfer torque with no slip. The felxplate is bolted to the crankshaft and then the torque converter to the flex plate. This one piece billet flex plate is SFI certified to 29.3.

Note: A SFI certified flexplate is required on drag racing vehicles running 11.99 and quicker the 1/4 mile and 7.49 and quicker in the 1/8 mile, or any vehicle exceeding 135mph. In 2008 it was changed from the 29.1 SFI specification to the 29.3 specification for automatic transmissions for diesel applications. The new rules for the flex plate require that the material cannot be stamped metal as are many OEM flex plates.

The Input Shaft

The input shaft is the first thing to go south with the Allison transmission. This Allison billet input shaft is built to withstand everything you can throw at it. This new Allison billet input shaft is manufactured from 9310 Vacumelt steel which increases torsional fatigue strength by over 50%. The SunCoast Allison billet input shaft is machined with a larger radius at the turbine spline for added strength. This a must for vehicles that are lifted with larger wheels and tires, for heavy towing and hauling, and vehicles with aftermarket turbos.

The Torque Converter

SunCoast Allison 1000 torque converters come in many varieties, from heavy hauling, sled pulling, drag racing, to daily driving. Here at SunCoast we design and manufacture all of our torque converters in house. Because of this unique advantage SunCoast can supply almost any request in regards to stall speed or torque multiplication. All of our SunCoast Allison triple disc converters are outfitted with a heavy Duty forged billet steel cover and give unbeatable lock up performance.

All of the SunCoast Allison 1000 torque converters come standard with custom pump and turbine modifications (in house). SunCoast also Tig Welds each individual furnace brazed fin for improved reinforcement. The SunCoast Allison billet triple disc converter also comes standard with our proprietary trapezoidal clutch teeth.

The Billet C2 Clutch Hub

The Allison transmission is an incredibly robust unit, however when exposed to conditions outside what it was designed for weak points begin to expose themselves. The factory C2 clutch hub has been known fail prematurely. This issue is most commonly seen in conditions where larger tire/wheel combinations, heavy towing/hauling, sled pulling, drag racing, and larger shock loads.

SunCoast replaces the factory C2 clutch hub with a much stronger billet piece that is manufactured from 4140 heat treated stress relieved steel. This new Allison billet C2 clutch hub has had the spline lengthened .125 for increased contact area. The spline boss diameter has also been increased .100 for added strength. This Allison billet C2 clutch hub is installed on all SunCoast 700 horsepower category 3 transmissions.

Billet Intermediate shaft

The factory intermediate shaft is one of the last hard parts to break typically on the Allison transmission.  SunCoast replaces this shaft on transmission that will be exposed to power levels above 750 horsepower. This new Allison billet intermediate shaft is made from a much stronger 300M billet material. This new billet intermediate shaft also feature an exclusive additional lubrication hole for the P3 sun gear and pilot increasing the life of that circuit. This SunCoast Allison intermediate shaft also has been gun drilled to provide a polished interior finish to eliminate any internal stress risers. This shaft is also heat treated for added strength and reliability.

Billet Output Shaft

The Allison output shaft can be subjected to a tremendous amount of torsional fatigue. This issue can be even more troublesome with heavy towing/hauling or when increasing horsepower and torque. SunCoast replaces the factory Allison output shaft with a billet piece on our Category 4 Allison rebuilds. This new Allison billet output shaft is machined from 300M billet steel and is a direct drop in replacement.

The Billet P2 Planet

The P2 planet with the Allison transmission can strip or snap as a result of poor tuning, shock load, improperly built transmissions and higher horsepower applications. This failure can and will result in catastrophic failure and ore immobility. The SunCoast P2 planet is the solution to the issue. This item is manufactured here at SunCoast using 4140 billet steel that is then induction hardened. This item is highly recommended for higher horsepower applications, including sled pulling, drag racing, as well as heavy Duty towing. This planet comes with a machine SunGear which is required for use of the planetary.

New internal wiring harness

Every build here at SunCoast reliability is our number one priority. Each one of our (Category) Allison Transmissions comes with a new internal wiring harness. As the transmission continues to age, the plastic connectors become brittle and will break during disassembly. This will eventually lead to premature failure.

Some other transmissions exclusives include SunCoast proprietary C1, C2, C3, and C4 Alto carbonite frictions/Rabestos SCZ frictions that contain no center slots. These frictions utilize a waffle pattern in the material to help retain oil helping the clutch cool when not applied. Redesigned apply pistons with improved rubber compounds proven to hold higher heat. This custom piston allows us to use a thicker spring apply plate which replaces the thin OEM one that will cone and cause uneven apply surface resulting in premature clutch failure. Custom SunCoast apply plate that redirects fluid to better lubricate frictions from the inside out which lubes the entire friction rather than OEM style that lubricates from the center out leaving the inner half of the clutch burnt. Includes exclusive smart trim / clutch control valve. Includes all items needed to modify the C2 clutch piston for increased clutch durability.

Transmission contains the following:

SunCoast custom clutch packs
SunCoast custom Steels
SunCoast custom billet plates
SunCoast custom overhaul kit
Recalibrated Valve body
SunCoast gasket kit
Pan Filter
Spin on filter
Pan gasket
SunCoast Filter Loc
New internal wiring harness
Billet input shaft
Billet intermediate shaft
Billet output shaft
Billet flexplate
Billet P2 planet
Billet C2 clutch hub
SunCoast Triple Disc Billet Converter

Reviews

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torque converter for 2006 lly duramax with allison 1000

bill marcos | 11/6/2021
These packages come with a modified stall converter.

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