With the August 2008 release of iRacing, ARCA08 quickly dropped off the radar for new drivers.
Drivers who continue to use ARCA08 instead of iRacing often cite one of the following reasons:

- Superior physics (car is in the track instead of on top of it)
- Multiplayer contact is possible and realistic (rubber bounces, metal scrapes, etc.)
- Low cost! No need to rent the game and pay for each track

Several updates to ARCA08 were published by TSF in 2008 that invalidated setups. Each time this was done, it disrupted league racing and frustrated drivers causing some of them to stop using the sim. In December of 2008, TSF partnered with Pragmatic Solutions to release ARCA08 through their Leverage Client digital rights management software. The Leverage Client roll-out was troubled by installation errors and was difficult to use once it was installed. The Leverage Client was responsible for a significant decrease in the number of drivers using ARCA08. Everyone had to re-install and many just gave up. In October 2009, a spotter plugin was released by the ARCA08 community. The spotter replicated the experience found in NR2003 and subsequent updates added tire limit tracking and admin utilities making two-wide restarts and wave-arounds possible.

In late 2009 and in subsequent years, the ARCA08 community released add-on tracks to complete the NASCAR schedule. TSF had been slow to provide these tracks and it was unclear if they planned to provide all tracks on the NASCAR schedule. Tracks were imported from rFactor and modified to work with ARCA08. TSF did not approve of these add-on tracks and threatened leagues that used them. TSF released Charlotte, Chicago, and Gateway after the league admins began releasing their own tracks.

In June 2011, TSF released the Gateway track and changed all tire model numbers which broke all of the non-TSF add-on tracks. The Gateway patch was the last software made publicly available by TSF. It was released as a ZIP file and not published using the Leverage Client. This caused great confusion and another driver exodus ensued. It was several years before TSF officially allowed add-on tracks. At first, they looked the other way and asked leagues not to publish themselves on the lobby when running non-TSF tracks. In early 2013, they lifted this restriction. By this time, about 6 leagues remained that could attract a 15-driver field.

In January 2010, TSF announced that they would be publishing an update called Professional Stock Car Simulator that would include trucks and a COT model. The expected delivery date was the end of 2010. It is not clear what happened to that project because it was supposed to be based on the updated engine from ISI developed for rFactor2. An addition to ARCA08 called the XPatch was announced in 2011. TSF got a group of beta testers to use the software in 2012 and planned a February 2013 release. Obtaining a copy of the beta XPatch was not easy (sign an NDA, install SVN, get online with a TSF rep to get an account, etc.), but many dedicated drivers tested and were excited by the graphical improvements (new shaders) and the different truck physics (less horsepower and more aero dependent).

In January 2013, a meeting was held between TSF and league admins. A TSF-sponsored truck series would be established upon the release of the XPatch and a community web site for results and schedules would be promoted. The web site (ARCASimRacingX.com) was built by community members, but the XPatch was not released and the TSF-sponsored series did not materialize.

By mid-2013, only 5 leagues remained and each struggled to achieve 10-car fields. TSF allowed someone who had previously converted tracks from rFactor to make changes to the XPatch software. Rather than completing the XPatch merger of the original ARCA car and the Trucks, the modder removed the ARCA car from the sim and replaced it with a "cup" car which used truck physics and a motor with ridiculous horsepower. At the end of 2014, the modder moved on to work on a different project and TSF stopped supporting the servers needed to download and register the sim. This gave the community an opportunity to pick up where TSF left off in 2012. The original ARCA car was restored, truck physics were completed, and a Cup car was added with proper geometry, weight, and horsepower. Stock Car Evolution (SCE) donated their 3D model for the Cup car body. The ASRX Launcher was built as the distribution and lobby mechanism. By the end of 2015, 40-60 drivers raced every night. In 2016, the Cup car was modified to simulate the low-downforce package introduced by NASCAR. In June of 2016, a Grand National car was added to the lineup that is a higher downforce, lower horsepower mod simulating the NASCAR Xfinity car. In 2017, the Cup car was modified to keep up with lower-downforce aeronydamics introduced by NASCAR. In 2022, the Gen7 car was added to simulate the 5-speed, independent suspension, and diffuser-generated downforce of the NASCAR NextGen car.