San Antonio's Trusted Transmission Specialists.

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Honest Repairs. Reliable Service.

Providing Greater San Antonio With Transmission Services For Over 40 Years

$10 Off Oil Change

$10 Off Oil Change

A full oil and filter change.  Includes our 24-point inspection!

May only use once per vehicle per year.
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$20 Off Brake Service

$20 Off Brake Service

Full brake service including pads and rotors.

Does not cover caliper replacement or brake lines.
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$29.95 A/C Inspection Special

$29.95 A/C Inspection Special

Full A/C Inspection Special for $29.95 

May only use once per vehicle per year.
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Flexible Financing Available

Let's keep you - and your car - moving forward.


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Our Core Values

What We Stand For at Guaranteed Transmission

Our values are the foundation of everything we do at Guaranteed Transmission. We believe in honesty, professionalism, and putting our customers first every step of the way. Our technicians are dedicated to continuous improvement, always staying updated on the latest technology and best practices. We work hard to build lasting relationships with our clients by delivering exceptional service, transparent pricing, and trustworthy advice. Your satisfaction and safety are our top priorities, and we back our work with warranties for your peace of mind.

Proud Member of the ATRA Association

As an ATRA association member, we follow a strict Code of Ethics and follow industry-leading repair standards for all transmission services.

Advanced Diagnostics. Comprehensive Care. Nationwide Peace of Mind.

Black-and-yellow ATRA logo for the Automatic Transmission Rebuilders Association

Our Services

Transmission and Auto Repair Services We Offer

Transmission Service

Transmission Service

Full-service transmission repair and maintenance in San Antonio—keep your vehicle running smoothly with our experts.
Engine Repair

Engine Repair

Comprehensive engine repair for all vehicles, restoring performance and reliability in San Antonio.
Computer Diagnostics

Computer Diagnostics

Advanced computer diagnostics for all vehicle systems—identify issues fast with San Antonio’s trusted experts.
Four-Wheel Drive Systems

Four-Wheel Drive Systems

Four-wheel drive system repair and maintenance in San Antonio—get ready for any road or adventure.
Vehicle Diagnostics

Vehicle Diagnostics

Pinpoint vehicle problems quickly with advanced diagnostics for all makes and models in San Antonio.
Check Engine Light

Check Engine Light

Check engine light on? Get fast answers and honest solutions from San Antonio’s transmission specialists.
Fluid Level Check

Fluid Level Check

Routine fluid level checks keep your vehicle protected and running smoothly in the Texas heat.
Electric Vehicle Service

Electric Vehicle Service

Certified electric vehicle service and repair for modern EVs and hybrids in San Antonio.
Diesel Repair

Diesel Repair

Specialized diesel repair for pickups and commercial vehicles, keeping San Antonio’s workhorses running strong.
Fleet Service

Fleet Service

Fleet maintenance and repair for San Antonio businesses—fast, reliable, and customized to your needs.

Customer Reviews from San Antonio Drivers

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Vehicle Makes We Service

Frequently Asked Questions

What types of vehicles do you service?
We service all makes and models, including domestic, import, hybrid, and diesel vehicles. Our technicians are experienced with a wide range of manufacturers and vehicle types.
Do you provide free estimates before repairs?
Yes, we always offer free estimates. We believe in transparent pricing and make sure you understand the cost and scope of work before any repairs begin.
Are your repairs backed by a warranty?
Absolutely. We stand behind our work with robust warranties on our transmission repairs and other services, giving you added peace of mind.
Can I wait at the shop during my repair?
Yes, our facility offers a comfortable waiting area with Wi-Fi and refreshments. Our staff will keep you updated on your vehicle's progress throughout your visit.
How do I know if I need transmission service?
If you notice unusual noises, shifting problems, or warning lights, it may be time for a diagnostic. Contact us for an expert evaluation and honest advice.

A Family of Trusted Brands

PROUDLY SERVING SAN ANTONIO

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