Last week news surfaced that General Motors had overstated the EPA ratings on approximately 60,000 crossovers. At the time of publication the company was framing the issue as one isolated to the 2016 Buick Enclave, Chevrolet Traverse and GMC Acadia. However, Consumer Reports and others are beginning to speculate that this issue goes deeper than just 2016 models.

A quick glance through the EPA’s website shows some interesting facts. Last week, prior to the realization about GM’s label ‘misprint’ the EPA was showing the following ratings for the GMC Acadia AWD:

2013 MY – 17/24 mpg

2014 MY – 16/23 mpg

2015 MY – 16/23 mpg

2016 MY – 15/22 mpg

Interestingly enough, those ratings have all changed on the EPA website as of the time of this publication. Now every model year is rated 16 mpg city and 23 mpg highway, except for the 2016 that’s rated at 15 mpg city and 22 mpg highway.

Industry watch site Daily Kanban noted in its report on the mater last week that as recently as January 2016 the EPA’s website was listing the ‘misprint’ figures for the 2016 models. This contradicts GM’s statement that the issue was a ‘data transmission’ error associated with the printing of their window stickers.

It is worth noting that these crossovers–known as the Lambdas–have not received any significant mechanical updates since 2013. GM has not even upgraded the 3.6-liter V-6, of which these vehicles are using a version of it that is two generations behind the latest 3.6-liter. Those familiar with GM RPO codes will understand that they are using the LLT V-6, whereas the latest version is the LGX.

However, a GM spokesman did tell Automotive News last week that the company had made some technical changes to the 2016 models that could have impacted the vehicles’ EPA figures. He was unable to detail the changes at the time.

AutoVerdict was able to confirm through GM’s online order guide that no significant changes were made to any of the 2016 models. Typically notable changes between model years are noted on the company’s order guides.

Naturally this situation is calling into question previous model years of the crossovers. Most publications (including this one) have found it difficult at best to achieve even close to the EPA ratings on these particular vehicles in real-world testing.

Overstated ratings would not be a new issue in the industry. Hyundai, Ford and others have been caught engaging in overstated EPA calculations in the past. Ultimately the automaker would fess up to the issue, then compensate owners for the difference associated with fuel costs. It’s far too early to tell if any of that will occur in GM’s case.