When Dow component Exxon Mobil (NYSE: XOM) said it will raise its quarterly dividend to 73 cents per share from 69 cents last month, the largest U.S. oil company not only boosted its dividend increase streak to 33 consecutive years, but alleviated investors’ about the impact of falling oil prices on energy sector dividends.

Exxon’s dividend increase helped it remain in the ProShares S&P 500 Aristocrats ETF (NYSEArca: NOBL) and the PowerShares Dividend Achievers Portfolio (NYSEArca: PFM), dividend ETFs that require payout increase streaks of 25 and 10 years, respectively. [Exxon Keeps its Place in Dividend ETFs]

However, some dividend and equity-based energy ETFs, including the largest, the Energy Select Sector SPDR (NYSEArca: XLE), still face another dividend issue and it comes courtesy of Chevron. Like Exxon, Chevron, the second-largest U.S. oil company, is a dividend aristocrat, qualifying it for membership in NOBL and easy admission to PFM. Exxon and Chevron combine for 28.6% of XLE’s weight.

However, some analysts do not view Chevron’s dividend outlook as being as sanguine as Exxon’s. In downgrading Chevron to sell from neutral Monday, Goldman Sachs noted that if oil stays below $60 per barrel, only Exxon can generate enough free cash flow to continually boosting its dividend.

We downgrade Chevron Corporation from Neutral to Sell – and lower our 12-month, multiples-based price target from $111 to $99 (5% total return downside vs. average Super Major total return of +4%) on lower earnings estimates. Three factors underpin our negative view on Chevron: (1) the company will struggle to generate free cash flow after the dividend under our new oil price forecast, limiting capital allocation potential; (2) we see downside risk to the Chevron’s 2017 production guidance; and (3) after multiple years of outperformance, Chevron’s relative P/E multiple to Buy-rated ExxonMobil appears stretched,” according to the Goldman note posted by Ben Levisohn of Barron’s.