Gasoline Specifications (U.S. and Canada Only)
At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada.
Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines containing MMT. See Fuel Additives on page 9‑41 for additional information.
See also:
Cellular and GPS Antennas
Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...
Under the Hood
The Yukon is available with either rear- or four-wheel drive. The Yukon
Denali can have an all-wheel-drive system that's distinct from the available
part-time four-wheel drive on the regular Yukon ...
When to Check and Change Automatic Transmission Fluid
It is usually not necessary to check the transmission fluid level.
The only reason for fluid loss is a transmission leak or overheated transmission. If a small leak is suspected, then use the followi ...