The big debate in the auto industry swirls around worries of whether a sales peak in the U.S. has been reached. With Autodata reporting sales rose only 0.7% overall, July sales give us some clues as major auto manufacturers posted flat sales or small declines over last year’s historic highs.

Here are four trends:

1. Pickup sales are holding up. With gas prices and interest rates still low, pickups remain relatively affordable for many buyers. There continues to be evidence that when Americans can afford them, they prefer them over cars.

“Light trucks remained the hottest segment for the industry in July,” said Bill Fay, group vice president and general manager of the Toyota division, in a statement.

Industry sales of crossovers and pickups continue to rise as consumers continue to turn away from passenger cars.

Ford sales analyst Erich Merkle said pickup sales accounted for 13% of industry sales in July — up 1% from last July – while sales of mid-size sedans accounted for 11% of industry sales – a decline of 1.5% from the same month a year ago.

Sales of Ford’s segment-leading F-Series pickups fell slightly, although only by 1% as the Dearborn automaker sold 65,657 of the popular pickups — a number that is still considered to be historically strong.

Fiat Chrysler Automobiles’ Ram truck brand showed gains of 5%. General Motors also posted generally strong sales for pick-ups despite a decline for the Silverado.

“Industry sales for trucks and utility vehicles are cooling off, but GM appears to be bucking the trend, posting record sales for models within those two segments,” Mark Williams, analyst for Kelley Blue Book, said today.

2. SUV sales could be softening. It was a tough month at Ford for SUVs. Sales fell 22% for Ford’s popular Ford Explorer mid-size offering and 10.2% for Ford Escape compact SUV.

“Once again, Ford’s sales were a mixed bag. Ford trucks continue to show up in spades, with Transit continuing to display gangbusters growth. F-Series sales were flat, but this could be a blip on the radar.” Akshay Anand, analyst for Kelley Blue Book, said today. “More troubling for Ford is the retail sales dip of 6 percent, as both SUVs and cars were down this month. The sedan trend likely will continue, but if Ford wants further sales growth, it must bring SUVs back into the black.”

But Fiat Chrysler Automobiles, which is under investigation for how it reports sales and restated its monthly sales last week going back more than five years, said Tuesday its sales increased by a narrow 0.3% in July, partly due to the strength of its Jeep SUV brand. Sales of the automaker’s popular Jeep and Ram brands both increased 5% while sales of all other brands declined.

3. Buyer incentives grow at faster rate than increase in transaction prices. Analysts with Kelley Blue Book say that so far this year, the growth in incentive spending by automakers has outpaced the increase in transaction prices — the industry term for the amount that buyers actually paid for a vehicle — for its cars and trucks.

Mark LaNeve, Ford’s vice president of U.S. sales and marketing, said General Motors started off the month with aggressive incentives on its pickups and a number of other models – including small and midsize crossovers – but said incentives for Fiat Chrysler’s Ram brand were about the same as usual.

“(GM incentives) really amplified the industry volumes for the beginning of the month. It wasn’t just pickup trucks. It was across the bulk of their lineup,” he said.

LaNeve predicted some automakers will deploy more aggressive incentives to protect their market share as industry sales begin to stall, even at historically high volumes.

“If you look at market shares (of all automakers) there actually has been very little movement,” in recent years, LaNeve said.

Many automakers were expecting sales to be a little stronger than they have been in recent months, he said, and as sales level off or decline, some automakers have excess inventory.

“So as that happens, the industry is going to want to protect its share and you get some escalation of incentives,” he said.

GM defended its strategy. “Our retail-focused plan is working and as availability of our new cars, trucks and crossovers continues to grow, we expect to keep our retail sales momentum going and our strong margins intact,” Kurt McNeil, GM’s U.S. vice president of sales operations, said. “We are growing our retail business while keeping inventories lean, incentive spend disciplined and growing our transaction prices faster than the industry average.”

GM’s temporary spike in incentive spending resulted from an eight-day sale in early July to begin the sell-down of several 2016 model year vehicles, the company said.  Its incentive spending average for the year is 11.4 %, compared to an industry average of 11 %, according to GM.

4. If auto sales are reaching a peak, that may not necessarily be an unhealthy or unsustainable thing in the near term. “I just think it has to be put in the context of overall levels…even though it wasn’t what we expected, we are still at an overall healthy level,” of industry sales, LeNeve said. “It was a historic run-up” over the past five to six years.

Karl Brauer, senior analyst for Kelley Blue Book said several automakers struggled to increase volume last month, despite two extra sales days in July and rising incentives on many models.