Alpharetta · Cumming · Forsyth County · North Atlanta

Transmission repair without the guesswork

Front-engine RWD and 4WD specialists — GM trucks especially, plus Ford, Dodge, and other American makes. Since 1986, every repair starts the same way: proper diagnostics. A solution, not a guess.

Mon–Fri 8 AM – 5 PM · 1025 Union Center Dr Suite E, Alpharetta, GA

What we do

Repair services

One shop, one standard — whether it’s a fluid service on a work truck or a full competition rebuild.

Diagnostics

Every repair starts with proper diagnostics — a solution, not a guess. We road-test, scan, and pressure-test before we recommend anything.

Repair & Rebuild

From a solenoid or a leak to a full performance rebuild, done in-house by the people who build 1,200 HP units for a living.

Replacement

When a rebuild doesn’t make sense, we’ll install the right replacement — including any unit on our performance ladder.

Fluid & Filter Service

Correct fluid, correct filter, correct level. The cheapest insurance your transmission can buy.

Torque Converter Service

Converter diagnostics, replacement, and stall-speed matching — from stock replacements to billet performance units.

Performance Upgrades

Shift kits, converters, coolers, and reprogramming. Make a stock transmission live behind real power.

Stop by

The shop

Address

1025 Union Center Dr Suite E
Alpharetta, GA 30004

Hours

Mon–Fri 8 AM – 5 PM

Phone

Transmission acting up?

Don’t drive it until it dies. Call now — diagnostics first, straight answers always.

1-year unlimited-mile warranty · Free shipping to most states · Custom builds to 1,500 HP

Transmission Repair in Cumming, GA

If your vehicle is slipping, shifting hard, or not moving the way it should, it’s time to have it looked at by a shop that works on transmissions every single day.

At Mad Dog Transmissions, we provide expert transmission rebuilds serving Cumming, Forsyth County, Alpharetta, and the North Atlanta area. We focus on accurate diagnostics and fixing the root cause—so the problem is solved the first time, not patched until it comes back.

Transmission Repair for GM, Ford & Dodge

We specialize in rear-wheel drive and 4WD transmission systems, with a strong focus on GM trucks and vehicles. We also regularly work on:

  • Ford transmissions
  • Dodge / Mopar transmissions
  • Other American-made RWD and 4WD vehicles

If your vehicle has a traditional front-engine, rear-wheel drive or 4WD drivetrain, there’s a strong chance we’ve built or rebuilt one like it before.

Common Transmission Problems

If you’re experiencing any of the following, it may be time to have your transmission checked:

  • Slipping gears
  • Hard or delayed shifting
  • Vehicle not going into gear
  • Grinding or unusual noises
  • Transmission fluid leaks
  • Check engine light related to transmission performance

Catching these issues early can mean the difference between a manageable job and a much bigger one—so it’s worth getting diagnosed sooner rather than later.

Do You Need a Transmission Repair or a Rebuild?

When people search for “transmission repair,” what they usually mean is simple: their transmission isn’t working right, and they want it fixed properly. Here’s our honest take on how to do that.

A quick patch—replacing a single part on a transmission that already has internal wear—often doesn’t hold. The underlying problem is still there, and a partial fix can actually compromise the rest of the unit. That’s why we don’t band-aid transmissions, and it’s why we stand behind a complete rebuild the way we can’t stand behind a piecemeal repair.

In a rebuild, we disassemble the transmission completely, inspect every component, replace what’s worn or failed, and reassemble it to perform like new. It’s a bigger job than swapping one part—but it fixes the actual cause, it lasts, and it’s backed by our warranty. On a vehicle you plan to keep, it’s the difference between fixing the problem once and chasing it repeatedly.

Every job starts with a proper diagnosis, so you’ll know exactly what’s wrong and what it’ll take to fix it before any work begins. We’ll always give you a straight answer.

Our Transmission Services

  • Transmission diagnostics
  • Complete transmission rebuilds
  • Performance transmission builds
  • Transmission replacement
  • Torque converter service

Every job starts with a proper diagnosis so you know exactly what’s going on before any work begins.

Why Choose Mad Dog Transmissions

Here’s something most local shops can’t say: Mad Dog builds high-performance transmissions rated up to 1,200 horsepower for customers across the country. When you bring in your truck or daily driver, that same race-grade expertise goes into your rebuild.

We’ve been building and rebuilding transmissions since 1986—nearly four decades under one roof. We’re not a general repair shop that also happens to touch transmissions; transmissions are all we do. We focus on the drivetrain systems we know best, especially GM rear-wheel drive and 4WD setups, so you’re getting a real solution from people who build these units for a living, not a guess.

Every rebuild is backed by our standard 1-year, unlimited-mileage warranty, with extended coverage available up to 3 years for an additional $300 per year. We stand behind our work because we know what goes into it.

Transmission Repair Forsyth County

Serving Cumming, Forsyth County & North Atlanta

  • Mad Dog Transmissions works with customers throughout:

    • Cumming
    • Forsyth County
    • Alpharetta
    • North Atlanta

    If you’re searching for “transmission repair near me,” we’re a local shop that focuses specifically on transmission work—not general auto repair.

Schedule Your Diagnosis

If your vehicle isn’t shifting correctly or you suspect a transmission problem, don’t wait—small issues get expensive fast. Contact Mad Dog Transmissions today to schedule a diagnostic and get a clear, honest answer on what your vehicle actually needs.

Frequently Asked Questions

What's the difference between a transmission repair and a rebuild?

When people search for transmission repair, they usually just want the problem fixed properly. A quick patch on a transmission that already has internal wear often doesn’t last and can’t be warrantied. That’s why we focus on complete rebuilds: we disassemble the unit, replace worn and failed components, and restore it to like-new condition. It’s a bigger job than swapping one part, but it fixes the real cause and it’s backed by our warranty.

How much does a transmission rebuild cost?

Cost depends on the vehicle, transmission model, and extent of the damage. We provide a clear quote after diagnosis, before any work begins.

How long does a transmission rebuild take?

Most jobs take a few days depending on parts availability and scope of work. We provide a realistic timeline at diagnosis.

Do you warranty your work?

Yes. Every rebuild comes with a 1-year, unlimited-mileage warranty standard. Extended coverage can be purchased for an additional $300 per year, up to 3 years.

What vehicles do you work on?

We specialize in American rear-wheel drive and 4WD vehicles, with a focus on GM trucks and cars. We also work on Ford and Dodge/Mopar transmissions.