Issue TSM-2026-09-14, Monday, September 14, 2026
The signal
Freight costs did not keep falling in August. BLS's not-seasonally-adjusted industry index for long-distance LTL trucking rose 4.48 percent from July to August 2026, from 293.695 to 306.839, reversing most of July's 4.63 percent drop. The index is now 14.31 percent above August 2025. Diesel moved harder: EIA's weekly US retail price hit 5.967 dollars a gallon for the week ending September 7, the highest weekly reading in EIA's series, which begins in March 1994, in nominal dollars, not adjusted for inflation. That is up 6.57 percent on the week and 30.34 percent above the early-July low of 4.578. BLS's August Producer Price Index release, published September 10, reports that seasonally adjusted prices for truck transportation of freight, a broader measure, advanced 2.0 percent for the month, and that diesel alone jumped 24.1 percent, over a third of August's rise in the final demand goods index.
Why it matters to shippers
Keep those two cost figures separate. The 4.48 percent move is the unadjusted LTL-specific index; the 2.0 percent move is the seasonally adjusted truck-transportation aggregate, a different series and scope. They agree on direction, and neither should stand in for the other on an invoice review. The practical risk is timing: when cost moves this fast, a rate negotiated weeks ago can go stale quickly, and an invoice reflecting a real increase can resemble one using the wrong rate or surcharge. Diesel is the clearest case: at 5.967 dollars a gallon, fuel costs can explain part of a genuine increase, but only the contract's surcharge table can show whether the invoice applied the right adjustment. Documentation, not a read of the headline number, is what tells the two apart.
The playbook
- Shipping: Pull the fuel surcharge table your contract names and check it against what this week's invoices applied. A real market move and a stale surcharge reference produce a similar-looking increase.
- Warehouse: Preserve the delivery receipt and bill of lading with the receiving record. If weight, classification, or piece count may be disputed, record the measured facts at the dock so finance has contemporaneous support for the invoice review.
- Finance and procurement: Check both the expiry date and the post-expiry terms of every negotiated LTL rate agreement. A higher charge after expiration is not automatically an overcharge; compare the invoice with the rate, tariff, or other authority the agreement says applied on the shipment date.
One question answered: who can file an overcharge claim, and what has to travel with it
Under 49 CFR 378.2(f), a claimant is "any shipper or receiver, or its authorized agent, filing a request with a carrier for the refund of an overcharge, duplicate payment, or overcollection." The definition expressly includes a receiver, but it does not settle every contract, payment, or authorization question about who should receive a refund. The claim must be filed in writing with the carrier that collected the charges (378.3(a)). Under 378.4(a), it must include the claimant's name, a file number if one exists, the refund amount when known, and enough information for the carrier to investigate. Section 378.4(b) requires the freight bill for an overcharge claim and says relevant supporting information may include the disputed rate, classification, commodity description, weight, tariff authority, or proof of payment. If the submission is incomplete, 378.4(d) says the carrier may not disallow it solely for that reason, and 378.5(c) requires the carrier to request the additional information it needs. For the fuller documentation picture, see LanePilot's guide to freight invoice audit and overcharge recovery.
LanePilot field note: contract expiry
An expired rate agreement changes the question from "what rate was negotiated?" to "what authority governed this shipment on its service date?" Expiration alone does not prove a billing error, and it does not prove that a published tariff automatically controls. The agreement may contain renewal, extension, replacement, or post-expiry terms. Review its effective dates, amendments, and any referenced tariff or rules before treating the difference as an overcharge. This is easy to miss when the market is moving: the LTL index rose 4.48 percent in four weeks and diesel rose 6.57 percent in a single week. A real market increase can make a contract-date problem look ordinary. Keep the agreement's effective dates beside the rate table, then compare each invoice with the version and authority that applied on the shipment date.
Sources and next step
BLS PPI, long-distance LTL trucking (FRED PCU484122484122, not seasonally adjusted, monthly). August 2026 value published September 10, 2026, same release date as the main PPI report; April through July revised. Method: tracks average prices received by long-distance LTL carriers. fred.stlouisfed.org/series/PCU484122484122
BLS Producer Price Index release, USDL 26-1495, August 2026, published September 10, 2026, seasonally adjusted unless stated. Method: monthly survey of price change received by domestic producers, by product and industry. bls.gov/news.release/ppi.nr0.htm
EIA weekly US retail diesel prices (FRED GASDESW, not seasonally adjusted, weekly, week ending Monday). Week ending September 7, 2026, released September 9, 2026; next release September 15, 2026. Method: weekly survey of retail fuel outlets nationwide, all taxes included. eia.gov/petroleum/gasdiesel
49 CFR Part 378, overcharge and duplicate-payment claim procedures, eCFR text current through September 11, 2026. Method: defines who may file a freight overcharge claim, what it must contain, and how the carrier must acknowledge and investigate it. ecfr.gov, title 49, part 378
Next step: LanePilot audits outbound LTL invoices against the original quote and drafts the dispute letter you file. Create a free account at lanepilottech.com/signup.