Cummins has spent most of 2026 raising its numbers, and the stock has spent the past three months ignoring it. Since the last report, which brought a third consecutive full-year guidance increase, record sales and a 10% dividend hike, shares have fallen 8.3% while the S&P 500 gained 1.2%. That disconnect is the story heading into the third-quarter release on November 5. The business narrative points up. The market is asking whether the peak is already in view.

The Street is looking for earnings of $8.38 a share on revenue of $9.89 billion. That would be growth of nearly 50% in profit and about 19% in sales from a year ago. Part of that comes from an easy comparison: North American heavy-duty truck volumes bottomed in last year's third quarter, when they were down roughly 40%. Still, sequential progress matters too. Revenue would need to climb from $9.46 billion in the second quarter, and earnings from $6.94. The Earnings Whisper of $8.30 sits a touch below consensus, a sign that the more informed bar is not stretched beyond published estimates. Management's latest full-year revenue outlook of $37.04 billion to $38.05 billion brackets the $37.30 billion consensus, but the Street is sitting in the lower half of that range. That leaves room for upside if the second-half ramp plays out as described.

Margins are where the quarter will be won or lost. Cummins lifted its full-year EBITDA margin target to 18% to 18.5%, yet the second quarter came in at 17.5%, down from 18.4% a year earlier, as tariffs and record-driven incentive pay ate into results. Hitting the annual target implies a meaningfully stronger back half. Management said incentive compensation should run about $25 million a quarter lower in the second half. A third-quarter margin at or above 18% would validate that math. Another print in the mid-17s would raise doubts about the guide, especially with engine margins already trimmed at the high end and distribution margins cut on slower parts growth.

Power systems remains the crown jewel. The unit posted record revenue of $2.3 billion with a 24.5% EBITDA margin, helped by data center demand that pushed China power generation sales up 88%. Capacity, not demand, is the constraint, with lead times stretching into the second half of 2028 and 20 gigawatts of added capacity under construction. Investors should look for evidence that new output is reaching customers and lifting shipments. They should also want updates on the multi-year hyperscaler agreement covering several gigawatts of backup gensets and the Terce Energy prime-power project in Texas. Those deals mark Cummins' push beyond standby power, and any sign that the pipeline is broadening would support the higher 2030 targets unveiled at May's analyst day.

The truck side carries its own test. Cummins raised its North American heavy-duty forecast to 240,000 to 250,000 units and lifted medium-duty and China truck outlooks, while EPA clarity on the 2027 rules replaced a feared demand cliff with a phased transition. Holding or nudging those forecasts higher would confirm the cyclical recovery has legs. Mining is the soft spot, cut to a range of down 5% to up 5% on elevated channel inventory, and further deterioration there would be the clearest crack in the story.

Sentiment has cooled noticeably, with bullish readings roughly halving from the prior quarter. The stock trades near $531, well below its 200-day average of about $604 and close to the bottom of its post-earnings range of $507 to $661. Expectations, in other words, have reset lower even as fundamentals improved. For Cummins to break that pattern, the third quarter needs to show that second-half margin expansion is real and that power generation capacity is converting into revenue. Deliver both, and another guidance raise becomes plausible. Fall short on margins, and the market's skepticism will look justified.