Rocks

For their fourth album the band left the usual Record Plant routine. They rehearsed at the Wherehouse in Waltham and cut six backing tracks there with a mobile studio, then returned to the Record Plant in late February 1976 for the rest and the vocals. Douglas said the lyrics were the hardest part and came last. A whip effect was made by swinging a cord among the microphones, and the spur sounds came from bells and tambourines on Tyler's boots. Perry has said he was very high on heroin when he wrote Back in the Saddle.

Tyler and Perry wrote Back in the Saddle, Rats in the Cellar, Get the Lead Out and Lick and a Promise. Tyler and Whitford wrote Last Child and Nobody's Fault, Tyler and Hamilton wrote Sick as a Dog, Perry alone wrote Combination, and Tyler alone wrote Home Tonight.

Singles were Last Child, Home Tonight and Back in the Saddle. The album reached number three in the United States, sold four times platinum, and was one of the first albums to ship platinum. Rolling Stone's John Milward thought it mostly pale remakes of earlier hits, and Christgau said the band imitated Led Zeppelin well. Popoff gave it ten out of ten, and in 1994 the Los Angeles Times critic Jon Matsumoto wrote that it was arguably the best heavy metal opus ever made. Rolling Stone placed it at number 176 on its 2003 list and number 366 in 2020. Guns N' Roses, Metallica and Nirvana have cited it, and Kurt Cobain listed it among his favorites.