Circle D Transmission

FSi Racing & Tuning

When you're ready to move forward with your custom rebuild, fill out our online form and we will reach out to you within 24 hours to discuss it! 👍

https://www.circledtrans.com/HighPerformanceVehicle

At Circle D Transmission, we are forever grateful for the brave men and women who made the ultimate sacrifice for our great country. As we fire up the grills and enjoy the long Memorial Day weekend with friends and family, let us never forget that freedom isn't free.

DID YOU KNOW.... 😲?

Towing heavier loads than your auto is rated for can lead to an early demise for your transmission. Know your limits and don't over-do it.

We custom-mounted a Tru-Cool auxiliary transmission cooler to maintain optimum transmission fluid temperature.

We appreciate you! 🤩

Our 6R80 Performance Rebuild (Exedy Stage 2 Clutch & Steel Kit) is rated up to 1200 RWHP

👉 Exedy Stage 2 Clutch & Steel Kit (Increased Clutch Capacity in 2-6, 3-5-R & 4-5-6) This Module will provide approximately 40% more clutch surface area compared to the OE plates/clutches.

👉 300M Billet Intermediate Shaft

👉 New OE Filter & Valve Body Plate. New Gaskets, Seals & Rings

👉 Valve Body is performance calibrated to CDT Specs

👉 CDT Lubrication Modifications

👉 Full Time Cooler Flow

👉 Transmission end play is set to CDT Specs

Contact us to discuss your custom rebuild ✨

https://www.circledtrans.com/6r80-performance-rebuilds

We are grateful for our customers. ✨

Look, we understand that you want to take your car from mild to wild 🫣--- without having to be the one to put in the work. Transmissions are tricky and if you are not 110% sure you know what you are doing, then you probably shouldn't try to tackle it on your own. 🥴

We conveniently offer high-performance rebuilds right in our shop.

Ready to chat about your custom rebuild? Reach out to us today! ✨

If you’re in the Houston area this Saturday, stop by CDS for their Open House. They will also have a raffle with all proceeds going to our ALS Circle of Friends - Dennis Sehorn Foundation. Tickets available to purchase on site Saturday.

Weather looks like it will be decent on Saturday, no rain till later in the evening or Sunday. Just 2 days away... we are excited to see everyone. Reminder on the Car show - please be respectful, no burnouts and we will be providing brunch so no donuts needed.

We will also have a raffle with all proceeds going to our ALS Circle of Friends - Dennis Sehorn Foundation. Tickets available to purchase on site Saturday. More details to come.

And.... we have the "Event" shirt free to all in attendance.

CDT Billet Reinforced Output Carriers include a 4140 billet steel drive plate to strengthen the spline area.
The drive plate is milled and contoured to the planetary housing to eliminate any possible separation under a load.
We recommend this product for vehicles producing over 750 RWHP, Nitrous, or Heavy Vehicles (including trucks, SUVs, and CTS-Vs).
www.circleDtrans.com
713-895-7019
M-F 7:00 am-5:00 pm CST
[email protected]

For the 6L80 and 6L90 transmissions, in addition to offering custom performance rebuild kits, we also offer clutch modules, Sonnax Heavy Duty 1-2-3-4 Piston, Sonnax Pressure Switch Installation Tool Kit, Sonnax Delco Bearing Kit and the Sure-Cool System with Active Bypass.
www.circleDtrans.com
713-895-7019
M-F 7:00 am-5:00 pm CST
[email protected]

CDT Level 4 build on this 2008 Corvette with 1000RWHP for . Our Level 4 Build includes a billet reinforced output carrier, billet intermediate shaft & 4-5-6 clutch hub by , added clutch capacity, and performance steels along with CDT performance valve-body modifications. With proper tuning, you can’t go wrong with a CDT Rebuild or a CDT Rebuild Kit for your high-horsepower 6L80 or 6L90 transmission.
www.circleDtrans.com
713-895-7019
M-F 7:00 am-5:00 pm CST
[email protected]

We love reading feedback from our clients...please leave us a review if you haven't done so. Thanks!

Google review of Circle D Transmission by Matt Ryan ★★★★★ "Very thorough analysis of the problem. Great communication and fixed what the dealer and another shop could not. Best Transmission shop in Houston"

Years of R&D have been invested in order to provide our clients with reliable 6L80 and 6L90 performance rebuild kits. These kits are proving to provide excellent results when paired with proper tuning of both the ECM and TCM. If you’re looking to transform your factory transmission to withhold more horsepower, this is the custom rebuild kit for you. Detailed instructions included!
www.circleDtrans.com
713-895-7019
M-F 7:00am-5:00pm CST
[email protected]

Starting 2024 with a Level 4 build on this 2010 Camaro SS that we originally built over 10 years ago. While this unit would still be functioning hadn’t a bushing spun out of the low-reverse housing, it was humbling to go back through and see where we started on the 6-speed automatics compared to where we are now. My oh my how our performance rebuilds have evolved over the years. With proper tuning, you can’t go wrong with a CDT Rebuild or a CDT Rebuild Kit for your high-horsepower 6L80 or 6L90 transmission.
www.circleDtrans.com
713-895-7019
M-F 7:00 am-5:00 pm CST
[email protected]

If you’re looking for an opportunity to leave your mark on the industry by working with one of the industry’s leading automatic transmission shops to rebuild high-performance transmissions and use your innovative skills to help take today’s transmissions to another level…we may have a solution for you!
If you’re looking for a shop that takes care of their customers and their team members…If you’re looking for an environment where team members say things like, “I’ve never worked in a shop like this before. It’s very professional!” If you have experience rebuilding 4L80/ 6L80 / 6L90 / 6R80 / 8L90 / 10L80 / 10L90 / 10R80 transmissions…WE WANT TO TALK TO YOU! Send an email to:[email protected]
www.circleDtrans.com
713-895-7019
M-F 7:00 am-5:00 pm CST
[email protected]

Another 5-star review from a repeat client!

Google review of Circle D Transmission by Dale Morin ★★★★★ "Friendly, professional and did a great job servicing my vehicle."

Another 6R80 transmission issue was solved with Lead Frame replacement.

Google review of Circle D Transmission by Jeff Keene ★★★★★ "I had a VERY common issue for F-150 owners. My transmission sensor was failing, which requires replacing a larger piece called the Molded Leadframe. Ford dealers don’t like to talk about it because it’s been the subject of recalls in the past, and they’ll quote you $1700 and a...

2019 Ford Raptor 10R80 CDT Performance Rebuild.
* Added clutch capacity in the C Clutch, D Clutch, E Clutch, and F Clutch.
* GPZ Clutches
* Modified CDF Drum
* New valve-body due to excessive pressure regulator valve wear
* Valve-body modifications include elevating line pressure, shift timing and TCC mods all to improve clutch apply
www.circleDtrans.com
713-895-7019
M-F 7:00am-5:00pm CST
[email protected]

6L80 Level 2.5 rebuild underway!

CDT Performance Transmission Rebuild on this 2015 Corvette Z06. It came in with delayed forward & reverse and the fluid was burnt. Upon an internal inspection of the transmission, we found burnt C1, C3 & C4 clutches. We used a 8L90 Rebuild Kit, installed a Billet Input Shaft, also used the GM updated pump stator and pump cover along with other CDT modifications. Killer engine and trans tune handled by
www.circleDtrans.com
713-895-7019
M-F 7:00am-5:00pm CST
[email protected]

CDT Custom Built Performance , Level 4, includes a Billet Reinforced Output Carrier. ZL1 Camaro - swipe to see the rebuild in progress.
www.circleDtrans.com
713-895-7019
M-F 7:30am-5:30pm CST
[email protected]

Circle D Transmission specializes in GM & Ford rear-wheel drive high-performance transmissions. We will custom build your transmission to match your application and any future horsepower increases.

www.circleDtrans.com
713-895-7019
M-F 7:30am-5:30pm CST
[email protected]

’68 Chevrolet Camaro with a CDT Custom Built behind this 6.2 Liter V8 Supercharged LSA Engine.
TransGo 4L80E-HD2 Reprogramming Kit
Controlled by PCS Controller

CDT performance rebuilds complete on these transmissions. Ford 10R80 & GM 10L90. 
www.circleDtrans.com
713-895-7019
M-F 7:30am-5:30pm CST
[email protected]

CDT 6L80 Level 4 Rebuild on this 2015 Chevy Truck with 800 RWHP. It came in with burnt 2-6, 3-5-R & 4-5-6 clutch packs and left with a complete rebuild with added clutch capacity, performance steels, billet reinforced output carrier, billet intermediate shaft, lots of other CDT performance modifications and a CDS 265mm multi-disc converter. On top of all that, we custom-mounted a Tru-Cool auxiliary transmission cooler to maintain optimum transmission fluid temp.