The Parts Manager's Checklist for Improving Hours-Per-RO in the Service Drive

Improving hours-per-RO starts with the parts department working backward from your technician schedule and labor targets, then building a systematic checklist to eliminate delays in parts availability, accuracy, and delivery to the bay. A parts manager who tracks on-hand inventory against your top 20 repairs, validates pick accuracy before tech pickup, and coordinates with the service advisor on parts lead times can easily add 0.3 to 0.7 hours per RO to your average, which compounds to real gross profit gains across a month.

What does hours-per-RO measure, and why should your parts manager care?

Hours-per-RO is the average number of labor hours sold per repair order. A store hitting 1.8 hours per RO is moving fast. One sitting at 1.2 is leaving money on the table. The connection to parts is direct: when a tech waits for a part, that RO gets extended, labor productivity drops, and you sell fewer hours despite being just as busy.

Your parts manager may not think of themselves as responsible for labor productivity, but they are. Every minute a technician sits idle waiting for a part is a minute that doesn't bill. Every inaccurate pick that sends a tech to the wrong bay or requires a comeback is a direct hit to hours-per-RO and to your ability to schedule the next job on time.

Consider a scenario: a technician has a typical $3,400 timing belt job on a 2017 Honda Pilot at 105,000 miles. The job should take 2.5 hours, which means you're selling $220 per hour in labor (assuming $88/hour labor rate). But if the timing belt cover bolts you ordered from the dealership haven't arrived, and the tech waits 45 minutes, that job now takes 3.25 hours of clock time but still bills at 2.5 hours. Your effective labor rate just dropped to $169 per hour. Multiply that across ten jobs a week, and you've given away thousands in margin.

A parts manager who owns this metric doesn't just receive orders and shelve them. They forecast demand, validate inventory accuracy, and design workflows that get parts to the bay on time, every time.

How should a parts manager build their hours-per-RO checklist?

The best checklist is one you build from your own data, but here's the backbone:

1. Audit your top 20 repairs by frequency and labor hours. Pull your last 90 days of ROs, sort by repair type, and identify which jobs happen most often and sell the most hours. A typical store might see timing belts, water pumps, brake jobs, oil changes with filter-service work, and transmission fluid services dominating. These are your "bread and butter" repairs.
2. Map the parts list for each. For each of those 20 repairs, print or pull the parts diagram and part numbers. Know what you stock, what you special-order, and what you get from the dealership. Write down average lead times for each supplier.
3. Check on-hand inventory accuracy. Count the actual parts in bins and compare to what your DMS or inventory system says. If your system shows 12 serpentine belts but you have 7, your data isn't reliable. Fix the count first.
4. Create a pre-service-day validation routine. The night before or first thing in the morning, look at the schedule. Check if the parts for tomorrow's jobs are in stock and in the right condition. If a timing belt kit is on the shelf but the gasket is back-ordered from the dealership, you need to know that before the tech pulls the engine apart.
5. Set a parts-delivery protocol. Define how parts move from your shelf to the service bay. Do you do a batch run at 8 a.m.? Do techs pick their own parts? Does a runner bring them to the bay? Whatever you choose, make it predictable and track compliance.
6. Establish a pick-accuracy check. Before a tech takes a part, someone verifies it's the right part for the right RO. A second set of eyes costs 30 seconds and prevents comebacks that cost hours.
7. Define your escalation path for parts delays. If a part isn't in stock and you can't get it same-day, who tells the service advisor, and when? The advisor needs to know early so they can adjust the schedule, call the customer, or offer a loaner. Surprises kill hours-per-RO.
8. Review the checklist weekly with your service manager. Schedule a 15-minute sync every Monday morning. Compare last week's hours-per-RO against the week before. Ask: where did we lose time? Was it parts-related? Adjust the next week's focus accordingly.

Which inventory practices have the biggest impact on hours-per-RO?

Not all inventory moves the needle equally. A parts manager has limited shelf space and cash tied up in stock. The smart move is to focus on the items that appear in your high-volume, high-labor repairs.

Stock the repeatable jobs heavily. If you do 8-10 brake jobs a month and they average 1.2 hours each, a complete brake job kit (pads, rotors, calipers, hardware, fluid, bleed kit) should always be on hand. A $180 brake pad inventory investment pays for itself in reduced wait time on two jobs. If you're waiting for pads from the dealership and losing 30 minutes per brake job, you're bleeding labor productivity.

Use a consignment or drop-ship model for slow-moving, high-cost items. Transmission filters, oxygen sensors, and fuel injector sets don't move every week, but when you need them, you need them now. Negotiate with your supplier to stock them at your location on consignment or to overnight ship them. Your cash flow improves, and your tech doesn't sit idle.

Track parts lead times by supplier and build a "sourcing hierarchy." For a given part number, know whether you should order from your in-house parts department, your primary wholesale supplier, the OEM dealership, or an online parts marketplace. Some parts come from in-house in 2 hours. Others from the dealership in 4 hours. Some overnight from a national supplier. Build this into your pre-service checklist so the service advisor or parts coordinator can set customer expectations accurately.

Implement a "missing parts" log. Every time a tech starts a job and the required part isn't in stock, write it down. Date, part number, frequency. After 30 days, you'll see patterns. If you're missing the same oil filter three times a week, it's not an accident—add it to your standing stock. If you're missing a specific transmission cooler line once a month, it's a sourcing problem, not an inventory problem. Fix what you can control.

And here's the honest truth: you cannot stock everything. The goal is to stock the parts that matter most to hours-per-RO and outsource the rest responsibly. This is the kind of workflow Dealer1 Solutions was built to handle—real-time visibility into which parts are holding up which jobs, so you can make smarter stocking decisions.

How should parts and service coordinate to prevent scheduling delays?

Hours-per-RO isn't a parts problem or a service problem. It's a coordination problem. When parts and service don't talk until a tech is already under the hood, you're reacting instead of planning.

Hold a weekly parts-and-service sync. Bring the parts manager, service manager, and one or two of your busier service advisors into a 20-minute meeting every Monday. Review:

• The previous week's hours-per-RO and any jobs that took longer than expected due to parts delays.
• The current week's schedule and any known parts challenges (backorders, long lead times, known supplier issues).
• Any new repair types or customer requests that might need parts that aren't currently in stock.

This isn't bureaucracy. It's the difference between a tech waiting 45 minutes for a part and that part being staged and ready before the job starts.

Create a pre-approval system for parts on multi-hour jobs. Before a customer approves a timing belt or transmission service, the service advisor should have already confirmed with the parts manager that all required parts are in stock or can be sourced by the agreed-upon completion date. No surprises. The estimate goes out with confidence, and the tech can start without waiting.

Use a shared visibility tool to flag parts issues in real time. If a tech discovers a job needs a part that's not in stock, they should be able to flag it immediately so the parts manager can source it while the tech moves on to the next job. Dead time becomes transition time instead.

Build a "fast-track" parts order process for rush situations. When a tech discovers a missing part mid-job, you need a clear path: call the dealership, call a local supplier, check the parts runner's next pickup, or authorize an emergency delivery. Define this ahead of time, not in the moment.

What metrics should a parts manager track weekly to measure hours-per-RO improvement?

You can't improve what you don't measure. A parts manager should own three to four key metrics and review them every week.

On-time parts availability rate. Of all the parts required for scheduled jobs, what percentage were in stock or sourced on time? Aim for 95% or higher. Below 90%, you have a systemic problem that's directly hurting hours-per-RO. Track this by parts category or supplier so you can see where the weakness is.

Pick accuracy rate. Of all parts picked for technicians, what percentage were correct on the first pull? A typical operation should see 98% or higher. If you're at 95%, one in 20 picks is wrong, which means comebacks, rework, and wasted labor. Implement a validation step and track compliance.

Days inventory outstanding (DIO) for top 20 parts. How long does a unit of your most-used parts sit on the shelf before it's consumed? If you stock 20 serpentine belts and sell 4 per week, DIO should be around 5 weeks. If DIO is 12 weeks, you're tying up cash and taking up space. If DIO is 2 weeks, you might be under-stocking and creating delays. Track this and adjust stocking levels monthly.

Average RO hours-per-RO by week, correlated to parts delays. This is the big number. Work with your service manager to get the weekly hours-per-RO. When it drops, ask: were there parts delays? If yes, drill into which parts and why. Use this to refine your checklist and stocking strategy.

Post these metrics in your parts area, share them in the weekly parts-and-service sync, and celebrate when they improve. A parts manager who goes from 91% on-time availability to 96% has directly added 0.4 hours per RO. That's a promotion-level contribution.

How do you handle special orders and backorders without killing your hours-per-RO?

Some parts you cannot stock. Transmission rebuilds, engine gasket sets, and specialized sensors come from the dealership or specialty suppliers and take days or weeks. You can't avoid backorders, but you can manage them so they don't surprise you mid-job.

Create a backorder protocol. The moment a part is ordered and you know it won't arrive in time for the scheduled job, the parts manager notifies the service advisor within 24 hours. The advisor then calls the customer with options: delay the job, do the work on a partial basis and finish later, or authorize a rental car. The customer chooses, but they choose before the tech is standing in the bay scratching their head.

Use a backorder tracking system. You need visibility into what's on order, when it's expected, and which ROs are waiting for it. Your DMS may have this built in, or you may need a simple spreadsheet. Either way, check it daily. If a part is late, escalate immediately.

Negotiate a "core parts" arrangement with your dealership or supplier. Some parts (alternators, starters, water pumps) can be ordered as "core exchange",you get a loaner part to install right away while your part is being rebuilt, and you return the old part when the new one arrives. This eliminates the delay entirely. If your supplier doesn't offer this, ask. They will, especially for high-volume items.

Build a network of local suppliers for emergency parts. Know which local independent parts shops, transmission shops, and machine shops can help you in a pinch. A transmission cooler line that the dealership can't get for three days might be available from a local shop by tomorrow. Keep these relationships warm.

What's the relationship between parts accuracy and your CSI scores?

This is a secondary benefit, but it matters. When a tech installs the wrong part or has to come back because a part was missing, the customer sees the entire job as unprofessional. A customer who had to reschedule because their brake job wasn't finished on time gives you a lower CSI score, leaves a bad online review, and may not return.

Parts accuracy and on-time delivery aren't just about hours-per-RO. They're about building a reputation for reliability. A parts manager who gets this right isn't just improving your labor metrics,they're building customer loyalty and repeat business, which is where real profit lives.

So the checklist isn't just operational. It's a reflection of your dealership's standards. A parts manager who takes ownership of hours-per-RO is taking ownership of the entire customer experience, and that's a mindset that separates average operations from best-in-class ones.

Frequently asked questions

What's a realistic hours-per-RO target for a typical service department?

Most dealerships see 1.4 to 1.8 hours per RO, depending on their service mix and the age of their customer base. Stores with more warranty work and recalls tend toward the lower end; stores with older vehicles and major repairs trend higher. A solid target is 1.6 to 1.7, which requires consistent parts availability and efficient scheduling. Track your baseline for 30 days, then set a target 0.3 hours higher and work toward it.

How much of an hours-per-RO improvement can we realistically expect from better parts management?

A well-run parts operation can add 0.3 to 0.7 hours per RO depending on your current state. If you're sitting at 1.2 and your parts availability is only 80%, you're probably leaving 0.4 to 0.5 hours on the table. Fix your top 20 parts stocking and validation, and you can recapture most of that within 60 days. The exact number depends on how much of your delay is parts-related versus scheduling, staffing, or shop capacity.

Should a parts manager be responsible for inventory costs if they're improving hours-per-RO?

Yes, but with a caveat. A parts manager should own both inventory investment and hours-per-RO improvement,they're connected. Stocking more parts improves hours-per-RO but increases carrying costs. The goal is to find the sweet spot: stock enough of your top 20 parts to hit 95% on-time availability, but don't overbuy. Use DIO and turnover rates to guide decisions. Many stores find that the revenue gain from higher hours-per-RO (even with slightly higher inventory) exceeds the carrying-cost increase.

What's the fastest way to identify which parts delays are hurting us most?

Pull your last 30 days of ROs and flag any that took longer than the standard time due to parts delays. Sort by frequency and labor hours lost. If timing belts account for 10 delays, water pumps account for 5, and brake jobs account for 3, focus on timing belt parts first. You'll get the biggest hours-per-RO gain by fixing the parts delays that affect your highest-volume, highest-labor repairs.

How do we prevent parts picks from holding up our morning schedule?

The key is a pre-service-day validation routine. The afternoon before or first thing in the morning, the parts manager reviews the day's schedule and stages or validates all required parts. Techs should not be searching for parts on the morning they're scheduled to use them. If you need a dedicated parts runner or staging area to make this happen, it's worth the investment. A 30-minute parts-staging effort in the morning prevents 2-3 hours of delays across the day.

Can a parts manager improve hours-per-RO if the service department isn't scheduling efficiently?

Parts management is necessary but not sufficient. If your service advisors are overbooking bays, scheduling techs without considering their skill level, or not respecting parts lead times, a parts manager can only help so much. The best results come when parts, service advisors, and technicians all align on the same goal. That alignment starts with the weekly parts-and-service sync and shared metrics.

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