While automakers selling cars in North America have been happy to accept the 2025 Corporate Average Fuel Economy standards, the same can't be said for similar plans in Mexico.

Last month we described how Toyota was refusing to support the new standards--and now Chrysler has joined the Japanese giant in shunning the new rules.

Mexico is trying to introduce a similar standard to that of the incremental CAFE requirements, requiring a carmaker's range to meet an average of 54.5 mpg by 2025.

35 mpg by 2016

The country has set a target for cars and light trucks of 35 mpg by 2016--set to save 18 billion gallons of fuel and reduce greenhouse gases by 170 million tons by 2030, according to the government.

But high profile automakers refusing to play ball could put the plans in jeopardy.

Automotive News reports that despite the targets harmonizing Mexico with the U.S. and Canada, automakers are describing the rules as "too strict".

An injunction granted to Toyota in September halted Mexico's efficiency plans, and while this was lifted last month, another injunction granted to Chrysler has once again put a wrench in the works. Several other companies as part of Mexico's local automakers association, AMIA, are also said to oppose the plans.

General Motors, Ford and Land Rover are all said to have submitted comments on the proposed standard. Land Rover filed no legal action, GM has declined to comment, and Ford did not respond.

Refusal isn't the whole picture...

It's possible that Chrysler's reasoning for refusing to support the standards is similar to that of Toyota, when we contacted the Japanese company last month.

Toyota's objection was that the Mexican government imposed the standards without consultation, and unlike the U.S, has proposed no incentives--including credits for automakers who meet the targets, and government-led customer incentives to encourage people into the greener vehicles.

The Toyota lawsuit was aimed at delaying the proposal while the AMIA discussed it with the government--and Chrysler's opposition will no doubt serve the same purpose.

Other concerns of the automakers include needing more lead time to develop models for the 2014 model year and later, and more flexibility due to Mexico's altitude--which makes meeting efficiency targets more difficult.

Unsurprisingly, the delays are frustrating environmental groups, both in Mexico and further afield.

Ultimately, it may take only small concessions from the Mexican government for the plans to go unhindered--but whether those concessions will be granted is currently unclear.


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