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Route 66 Auto Repair in Upland finds and fixes transmission fluid leaks. The hard part is finding the source, because fluid travels. A drip at the back of the pan may start at a cooler line, a seal or even the engine. Our ASE-certified technicians clean the area, add dye when needed, and trace it before quoting. You pay for the part that is actually leaking, not a guess.
Is that puddle transmission fluid?
Transmission fluid is usually red or pink when fresh and turns brown with age.
- Red, pink or brown spots under the middle or front of the car
- A slick, slightly sweet or oily smell, different from coolant
- Low fluid on the dipstick, or slipping after the car sits
- Wet film on the transmission case or bellhousing
- Smoke or a burnt smell after driving
How do we find where the fluid is coming from?
We start by cleaning the transmission and surrounding parts, because old grime hides fresh fluid. Then we run the engine, shift through the gears and look. If the leak is slow, we add a fluid-safe dye and ask you to drive a day or two. Under a UV light, the dye glows right at the source.
Common sources are the pan gasket, the cooler lines, the axle or output seals and the front pump seal. A leak between the engine and transmission may be engine oil, which is covered under engine oil leak repair. We photograph the source so you can see it.
Our leak repair process
Step 1: Clean and inspect
The area is degreased so fresh fluid is easy to spot.
Step 2: Trace with dye if needed
Slow leaks get a dye test and a short drive.
Step 3: Photograph and quote
You see the source and get a written estimate for that exact repair.
Step 4: Repair and recheck
After the fix, the fluid is topped off and the area is checked again after a road test.
What's included in leak repair
Included on the work order
- 01Degrease of the transmission area
- 02Running leak inspection
- 03Dye trace when the leak is slow
- 04Photo of the leak source
- 05Seal, gasket or line repair as quoted
- 06Fluid top-off and post-repair recheck
Which leaks can wait?
Need now: call
- Fluid dripping onto the exhaust
- A leak that drops the level enough to slip
- Puddles every time you park
Need later: book
- A damp gasket with no drips
- A slow seep you can monitor at oil changes
How leak repair is priced
Finding the leak is part of the diagnostic, and that fee is stated at the counter and applies to approved related repair. The repair price depends on the source: a pan gasket is quick, while a front pump seal needs the transmission out. Your written estimate names the part and the labor. AAA members save 10% on parts and labor, up to $75.
After the repair
Place a piece of cardboard under the car overnight for a few days. Clean cardboard means the job held. If there is a new spot, bring the cardboard in; it helps us see where it is dripping.
Frequently asked questions
Is it safe to drive with a transmission leak?
A slow seep is usually fine for a short time if you watch the level. A fast leak or one that drips on the exhaust is not. Call us at (909) 608-7699 if you are unsure.
Can stop-leak additives fix it?
Some can swell seals briefly, but they do not fix cracked or torn parts and may affect shifting. We prefer to repair the source.
Why did the leak start after a fluid service?
An overfilled transmission can push fluid out of a vent or seal. A loose drain plug or pan bolt is another cause. We check the level and fittings first.