# Fluid Level Checks in Upland > Fluid level checks in Upland covering oil, coolant, brake, power steering, transmission, differential and transfer case fluid, with leaks noted. Source: https://route66autorepairshop.com/drivetrain-and-additional-mechanical-services/fluid-level-checks Updated: 2026-09-17 Business: Route 66 Auto Repair, 1775 W Foothill Blvd, Upland, CA 91786, (909) 608-7699 Hours: Monday to Friday 8 AM–5 PM, Saturday 8 AM–2 PM, Sunday closed **TLDR:** We check engine and **driveline fluids**, including the differential and transfer case, and treat a **low level as a clue** to a leak. Route 66 Auto Repair in Upland checks the fluids your vehicle depends on, including the ones under the car that most quick stops skip: differential gear oil, transfer case fluid and manual gearbox oil. A low level is a clue, not just a chore. It usually means a leak or consumption, and we tell you which. ASE-certified technicians note each level and condition on your repair order and mark anything that needs attention as need-now or need-later. ## Which fluids do we check? - Engine oil level and whether it looks thin, dark or milky - Coolant level in the reservoir, checked cold - Brake fluid level and color - Power steering fluid on hydraulic systems - Automatic transmission fluid where there is a dipstick or check plug - Front and rear differential gear oil at the fill plug - Transfer case fluid on four-wheel and all-wheel-drive vehicles ## Why check differential and transfer case fluid? These fluids sit in housings underneath the vehicle with no dipstick, so they get forgotten. Gear oil that runs low from a seeping axle seal lets the gears run hot. You often hear the result later as a whine that rises with speed. Checking takes removing a fill plug on the lift, so it fits well with other underbody work. Trucks that tow up the grades on the 15 or pull boats to the river work their differentials hard. If you see a wet cover or seal, we write it down, even if the level is still full, so you can plan a repair before it turns into [differential repair](https://route66autorepairshop.com/suspension-and-steering-services/differential-repair). ## Our fluid level check process 1. **Under the hood:** We check oil, coolant, brake, power steering and washer levels and look at the color and smell. 2. **On the lift:** We open the fill plugs on the differential and transfer case and look for wet seals and gaskets. 3. **Top off or flag:** We top off what is approved with the fluid your vehicle specifies and flag any level that dropped for a reason. 4. **Write it down:** Each fluid's level and condition goes on the repair order with a need-now or need-later label. ## What's included in a fluid level check - Level and condition check of under-hood fluids - Differential and transfer case fill plug check on the lift - Leak check around seals, gaskets and hoses - Top-off with the fluid your vehicle specifies, as approved - Written notes on each fluid ## Is a fluid problem need-now or need-later? **Need now:** - Brake fluid below minimum or a soft pedal - Coolant dropping between visits or a sweet smell - Engine oil off the bottom of the dipstick **Need later:** - Dark fluid that is still at the correct level - A light seep at a differential cover with the level still full - Washer fluid that is low ## How pricing and timing work for fluid checks A fluid level check is often done during an [oil change](https://route66autorepairshop.com/oil-change-services) or another visit on the lift. Top-offs are charged for the fluid used. If a level points to a leak, finding the source is a separate diagnosis, and the fee is stated at the counter before testing. Flushes and fluid changes are quoted in writing first. AAA members get 10% off parts and labor, up to $75. ## After your fluid check If we topped off a fluid that was low, look under the car where you park for the next week. Watch for new spots and note the color. Red often means transmission or power steering fluid, green or orange often means coolant, and dark brown often means oil or gear oil. Take a photo and call us. A detailed condition test is available as a [fluid level inspection](https://route66autorepairshop.com/diagnostics-and-inspections/fluid-level-inspection). ## Frequently asked questions ### If you top it off, is the problem fixed? Not if the fluid went somewhere. Engines use some oil, but brake fluid and coolant should not drop much. We top off and tell you if the drop points to a leak, so you can decide on a diagnosis instead of topping off forever. ### How often should fluids be checked? Checking at each oil change is a good habit, and before any long trip or towing job. Heat in the Inland Empire summer makes low coolant and old fluids more likely to cause trouble. ### Can you check a transmission with no dipstick? Yes. Many newer transmissions are checked at a fill plug with the vehicle level and the fluid at a set temperature. We follow the manufacturer's procedure and tell you if it needs extra time. --- Call (909) 608-7699 or visit https://route66autorepairshop.com/contact for a written estimate.