A trip to AT&T Stadium last September told the Giants everything about their offensive line.

The Cowboys’ defensive front should provide a dose of truth serum once again on Sunday.

The Giants believe their offensive line is improved this season, a necessity if they are to make a jump up from the basement of the NFC East, but a day against the Cowboys will do the talking better than anyone wearing blue could pregame.

“I don’t know, we’re going to find out on Sunday,” right tackle Mike Remmers said Friday when asked what the line will do well. “We’ll see. I have some thoughts on it, but you just never know how it’ll actually look on film. I’m feeling really confident and excited though.”

Remmers, who deemed himself healthy and will play Sunday after missing Wednesday’s practice, and right guard Kevin Zeitler were acquired in the offseason to solidify the right side of a line that has been especially unstable in recent years. Left tackle Nate Solder and left guard Will Hernandez played every single snap next to each other last season and should be better off for it. And center Jon Halapio is back healthy again after breaking his leg and ankle against these Cowboys in Week 2 last year.

Offensive line coach Hal Hunter said the addition of veterans like Remmers and Zeitler makes for “a lot loss questions” entering this season. They won’t have to wait long to get their answer, either.

“We feel like we’ve made improvements,” coach Pat Shurmur said. “We’ll get to see how far we’ve come here Sunday.”

“Sunday Night Football” in Arlington last year was a nightmare for the Giants, and it all started up front. The starting offensive line of Solder, Hernandez, Halapio, Patrick Omameh and Ereck Flowers gave up six sacks and failed to open enough holes for a rushing attack that finished with a season-low 35 yards. Eli Manning was harassed and rarely had time to throw downfield, forcing him to dump the ball off to Saquon Barkley for a franchise-record 14 catches.

By the time the Giants played again in Week 3, Flowers had lost his starting job at right tackle and Halapio was out for the season. It was only the start of a turbulent season for a unit that allowed 47 sacks.

Hunter pointed to the line still being new last year against the Cowboys — not that it isn’t this time around — but believes their combined experience will help on Sunday.

“Remmers played in a Super Bowl before. Playing in Dallas isn’t going to faze him,” Hunter said. “… We have to make sure we can play with a lot of composure come Sunday.”

Remmers’ experience might not be worth as much if he didn’t have his health, but he said he was feeling “excellent” Friday. The 30-year-old had offseason back surgery and when he missed practice Wednesday, he was listed on the injury report because of “illness/back.” He was a full participant on Friday, though, insisting that Wednesday’s absence was due to illness and that his back was “100 percent.”

How the offensive line will be feeling after Sunday’s game remains to be seen. It is tasked with fending off a fast and strong defensive front that includes DeMarcus Lawrence — who has not been shy about how much he likes playing Manning — Tyrone Crawford and Jaylon Smith.

“[Lawrence is] a heck of a player,” Remmer said. “Not just him, but the entire D-line. Not just the D-line, and their linebackers, they bring a lot of different varieties of stuff. It’ll be a good test for us. They got an abundance of stuff. They bring a lot of different blitzes and stunts and twists. So you really gotta be ready for everything.”

Ready or not, here they come.