Editing Sum 41 (section)

===2006–2008: Baksh's departure and ''Underclass Hero''===
{{Main|Underclass Hero}}
On May 10, 2006, [[Dave Baksh]], via a statement through management, announced that he was leaving Sum 41 to work with his new band, [[Brown Brigade]], which has a more "classic metal" sound.<ref name="Exclaim Gormely"/><ref name="Baksh Departure">{{cite web|first=James|last=Montgomery|url=http://www.mtv.com/news/1531654/sum-41-guitarist-quits-group-to-focus-on-new-metal-band/|title=Sum 41 Guitarist Quits to Focus on New Band|work=[[MTV]]|date=May 12, 2006|access-date=January 31, 2023|archive-url=https://web.archive.org/web/20151016210154/http://www.mtv.com/news/1531654/sum-41-guitarist-quits-group-to-focus-on-new-metal-band/|archive-date=October 16, 2015|url-status=dead}}</ref> Baksh cited "creative differences" as the reason for his departure, but claimed that he was still on good terms with the band.<ref name="Baksh Departure"/>
The next day, Whibley confirmed Baksh's official departure and announced that the band would only replace him with a touring guitarist, who would not have any decision-making power in the band or be in videos, photo shoots, or albums.<ref name="official website 2">{{cite news|first=Deryck|last=Whibley|url=http://www6.islandrecords.com/sum41/www2/bbs/bbs1_7/thread.php?site_num=11&thread_num=14386018&folder_num=23&id=443188337988%20http://www6.islandrecords.com/sum41/www2/bbs/bbs1_7/...read_num=14386018&folder_num=23&id=443188337988|title=Sum 41 Board Message|work=Island Records|date=May 12, 2006|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20090408225827/http://www6.islandrecords.com/sum41/www2/bbs/bbs1_7/thread.php?site_num=11&thread_num=14386018&folder_num=23&id=443188337988%20http://www6.islandrecords.com/sum41/www2/bbs/bbs1_7/...read_num=14386018&folder_num=23&id=443188337988|archive-date=April 8, 2009|url-status=dead}}</ref> The band hired [[Gob (band)|Gob]] frontman and guitarist [[Tom Thacker (musician)|Tom Thacker]] to replace Baksh.<ref name="Exclaim Gormely"/><ref name="official website 2"/>
[[File:Sum 41 live 2008.jpg|thumb|left|230px|Sum 41 playing live at Club Oxygen on March 7, 2008]]

On April 17, 2007, the band released a song on [[iTunes]], "[[March of the Dogs]]".<ref name="March of the Dogs AP">{{cite web|url=http://www.altpress.com/index.php/news/entry/archive_1969|title=New Sum 41 album gets title, release date|work=[[Alternative Press (magazine)|Alternative Press]]|date=April 16, 2007|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20160826061322/http://www.altpress.com/index.php/news/entry/archive_1969|archive-date=August 26, 2016|url-status=dead}}</ref><ref name="George W. Bush">{{cite web|first=James|last=Montgomery|url=https://www.mtv.com/news/h7uyxo/sum-41-kill-president-in-new-song-deryck-whibley-says-its-a-metaphor|title=Sum 41 Kill President In New Song -- Deryck Whibley Says It's 'A Metaphor'|work=[[MTV]]|date=April 23, 2007|access-date=January 31, 2023|archive-url=https://web.archive.org/web/20230223140344/https://www.mtv.com/news/h7uyxo/sum-41-kill-president-in-new-song-deryck-whibley-says-its-a-metaphor|archive-date=February 23, 2023|url-status=dead}}</ref> Whibley was threatened with deportation from the United States for the song, because he metaphorically "killed the [[George W. Bush|president]]" on it.<ref name="George W. Bush"/><ref>{{cite web|author=Sowing|url=https://www.sputnikmusic.com/review/79851/Sum-41-Order-In-Decline/|title=Review: Sum 41 - Order In Decline|work=Sputnikmusic|date=July 19, 2019|access-date=January 31, 2023}}</ref> The band's fourth studio album, ''[[Underclass Hero]]'' was released on July 23, 2007.<ref>{{cite web|first=Kate|last=Sharp|url=https://www.bbc.co.uk/music/release/6vxm/|title=Sum 41 Underclass Hero Review|work=[[BBC]]|access-date=September 27, 2023|archive-url=https://web.archive.org/web/20231012161129/https://www.bbc.co.uk/music/reviews/6vxm/|archive-date=October 12, 2023|url-status=live}}</ref>

The album, backed by the first single and title track, "[[Underclass Hero (song)|Underclass Hero]]", was released on July 24, 2007.<ref name="George W. Bush"/><ref name="March of the Dogs AP"/><ref>{{cite web|first=Stephen Thomas|last=Erlewine|url=https://www.allmusic.com/album/underclass-hero-mw0000584729|title=Sum 41 Underclass Hero|work=[[AllMusic]]|access-date=June 27, 2019|archive-url=https://web.archive.org/web/20160306100928/https://www.allmusic.com/album/underclass-hero-mw0000584729|archive-date=March 6, 2016|url-status=live}}</ref> Despite mixed reviews,<ref>{{cite web|url=https://www.metacritic.com/music/underclass-hero/sum-41|title=Underclass Hero Reviews|website=Metacritic|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20230407072655/https://www.metacritic.com/music/underclass-hero/sum-41|archive-date=April 7, 2023|url-status=live}}</ref> the album was a commercial success, debuting at number seven on the [[Billboard 200|''Billboard'' 200]]<ref name="Chart History"/> and at number one on the ''Billboard Rock Albums'' chart, the band's highest US chart position to date.<ref>{{cite magazine|url=https://www.billboard.com/artist/sum-41/chart-history/rck/|title=Sum 41 (Rock Albums)|magazine=[[Billboard (magazine)|Billboard]]|date=October 6, 2007|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20230409142352/https://www.billboard.com/artist/sum-41/chart-history/rck/|archive-date=April 9, 2023|url-status=live}}</ref> It also peaked at number one on the Canadian Albums chart<ref name="Canadian Albums"/> and on the ''Alternative Albums'' chart.<ref>{{cite magazine|url=https://www.billboard.com/artist/sum-41/chart-history/alt/|title=Sum 41 (Alternative Albums)|magazine=[[Billboard (magazine)|Billboard]]|date=October 6, 2007|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20230409100612/https://www.billboard.com/artist/sum-41/chart-history/alt/|archive-date=April 9, 2023|url-status=live}}</ref> Two more singles were released from the album, "[[Walking Disaster]]"<ref>{{cite web|url=https://www.antimusic.com/news/07/aug/0208.shtml|title=Sum 41 Debut in Top 10|work=antMusic|date=August 2, 2007|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20230415160939/https://www.antimusic.com/news/07/aug/0208.shtml|archive-date=April 15, 2023|url-status=live}}</ref> and "[[With Me (Sum 41 song)|With Me]]".<ref>{{cite magazine|url=https://www.billboard.com/artist/sum-41/chart-history/can/|title=Sum 41 Billboard Canadian Hot 100|magazine=[[Billboard (magazine)|Billboard]]|access-date=September 27, 2023|archive-url=https://web.archive.org/web/20231002232358/https://www.billboard.com/artist/sum-41/chart-history/can/|archive-date=October 2, 2023|url-status=live}}</ref> ''Underclass Hero'' was certified Platinum in Canada.<ref>{{cite web|url=http://www.musiccanada.com/GPSearchResult.aspx?st=&ica=False&sa=sum%2041&sl=&smt=0&sat=-1&ssb=Artist|title=Gold and Platinum Search|work=[[Music Canada]]|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20131004214237/http://www.musiccanada.com/GPSearchResult.aspx?st=&ica=False&sa=Sum%2041&sl=&smt=0&sat=-1&ssb=Artist|archive-date=October 4, 2013|url-status=dead}}</ref> On September 15, 2007, the band headlined the [[House of Blues]] with [[Yellowcard]].<ref name="Yellowcard">{{cite web|first=Joe|last=Tone|url=https://www.clevescene.com/music/pop-punk-paradise-sum-41-and-yellowcard-at-house-of-blues-cleveland-1558511|title=Pop-Punk Paradise: Sum 41 and Yellowcard at House of Blues Cleveland|work=[[Cleveland Scene]]|date=September 13, 2007|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20230415162441/https://www.clevescene.com/music/pop-punk-paradise-sum-41-and-yellowcard-at-house-of-blues-cleveland-1558511|archive-date=April 15, 2023|url-status=live}}</ref>

In October 2007, the band began the ''Strength in Numbers Tour'', a tour of Canada with Canadian band [[Finger Eleven]]; [[Die Mannequin]] opened each of Sum 41's shows.<ref name="chartattack">{{cite web|first=Michelle|last=Singerman|url=http://www.chartattack.com/news/2007/10/23/deryck-whibleys-weak-back-ends-strength-in-numbers-tour-early/|title=Deryck Whibley's Weak Back Ends Strength in Numbers Tour Early|work=Chart Attack|date=October 23, 2007|access-date=February 6, 2009|archive-url=https://web.archive.org/web/20150923222508/http://www.chartattack.com/news/2007/10/23/deryck-whibleys-weak-back-ends-strength-in-numbers-tour-early/|archive-date=September 23, 2015|url-status=usurped}}</ref> During the tour, Whibley sustained a [[herniated disk]].<ref name="chartattack"/> As a result, the group cancelled the rest of its shows.<ref name="chartattack"/> After Whibley recovered from his injury, the band continued the ''Underclass Hero'' tour in March 2008 and toured until early July, when the group began preparation for its next album.<ref>{{cite web|first=Lindsey|last=Rivait|url=http://pastthepages.ca/080319/feature.html|title=Sum 41: the Underclass Heroes bounce back|work=The Lance|date=March 19, 2008|access-date=August 17, 2008|archive-url=https://web.archive.org/web/20080326231650/http://pastthepages.ca/080319/feature.html|archive-date=March 26, 2008|url-status=dead}}</ref>

Sum 41 released a greatest hits album in Japan titled ''[[All the Good Shit|8 Years of Blood, Sake and Tears]]'' in November 2008.<ref name="8 Years of Blood, Sake and Tears">{{cite web|first=Josiah|last=Hughes|url=http://www.exclaim.ca/articles/generalarticlesynopsfullart.aspx?csid1=127&csid2=844&fid1=34690|title=Sum 41 Release Japan-Only Greatest Hits Album|work=[[Exclaim!]]|date=November 6, 2008|access-date=November 7, 2008|archive-url=https://archive.today/20120729113116/http://www.exclaim.ca/articles/generalarticlesynopsfullart.aspx?csid1=127&csid2=844&fid1=34690|archive-date=July 29, 2012|url-status=dead}}</ref> The album included a previously unreleased song, "Always", and a DVD, which contains each of the band's music videos.<ref name="8 Years of Blood, Sake and Tears"/> On March 17, the band released the worldwide version of the album, titled ''[[All the Good Shit]]''.<ref>{{cite web|url=http://www.chartattack.com/news/2009/02/06/sum-41-hits-collection-goes-worldwide/|title=Sum 41 Hits Collection Goes Worldwide|work=[[Chart (magazine)|ChartAttack.com]]|date=February 6, 2009|access-date=February 6, 2009|archive-url=https://web.archive.org/web/20130408101252/http://www.chartattack.com/news/2009/02/06/sum-41-hits-collection-goes-worldwide/|archive-date=April 8, 2013|url-status=usurped}}</ref><ref>{{cite web|first=Stephen Thomas|last=Erlewine|url=https://www.allmusic.com/album/all-the-good-sh-14-solid-gold-hits-2000-2008-mw0000812657|title=Sum 41 All the Good Sh**: 14 Solid Gold Hits 2000-2008|work=[[AllMusic]]|access-date=April 2, 2022|archive-url=https://web.archive.org/web/20201026063314/https://www.allmusic.com/album/all-the-good-sh-14-solid-gold-hits-2000-2008-mw0000812657|archive-date=October 26, 2020|url-status=live}}</ref>