New TSB L-SB-0048-25 for transmission downshift clunk
Just saw someone posted this over at reddit. If someone had it done already, any issues afterwards?
The description sounds like what I'm experiencing when slowing/coasting to a stop for 5-4 or 5-3 downshifts although its less noticable after 10-15 minutes of warmup.
The description sounds like what I'm experiencing when slowing/coasting to a stop for 5-4 or 5-3 downshifts although its less noticable after 10-15 minutes of warmup.
Just released yesterday apparently so probably why nothing shows up on google. Post with screenshot of the TSB: https://www.reddit.com/r/Lexus/comme...wnshift_clunk/
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I guess not. I wouldn't bother unless it's an issue for you. If nothing else, it seems like this issue doesn't grenade the transmission after a few thousand miles (if mine is anything to go by). Mine has done it since day 1, over 2.5 years and 23,000 miles ago.
Toyota/Lexus is such a mess. Their inconsistency when it comes to listening to customers is absolutely infuriating. Follow my logic:
(+) they come out with the IS500 (V8)
(-) they keep a 10 year old interior and transmission
(+) they extend the life of the IS in 2026
(-) they make the exterior worse
(+) they update the interior
(-) they drop the V8 from the next IS
(+) they release a TSB for the IS500 transmission
That's just the IS lineup in a nutshell. Don't even get me started on their boneheaded decisions regarding the ES, RC, LS, and GS.
I would argue a well-tuned transmission would cause less wear because when you mash the pedal everything is just smoother - I could be wrong though.
Toyota/Lexus is such a mess. Their inconsistency when it comes to listening to customers is absolutely infuriating. Follow my logic:
(+) they come out with the IS500 (V8)
(-) they keep a 10 year old interior and transmission
(+) they extend the life of the IS in 2026
(-) they make the exterior worse
(+) they update the interior
(-) they drop the V8 from the next IS
(+) they release a TSB for the IS500 transmission
That's just the IS lineup in a nutshell. Don't even get me started on their boneheaded decisions regarding the ES, RC, LS, and GS.
Toyota/Lexus is such a mess. Their inconsistency when it comes to listening to customers is absolutely infuriating. Follow my logic:
(+) they come out with the IS500 (V8)
(-) they keep a 10 year old interior and transmission
(+) they extend the life of the IS in 2026
(-) they make the exterior worse
(+) they update the interior
(-) they drop the V8 from the next IS
(+) they release a TSB for the IS500 transmission
That's just the IS lineup in a nutshell. Don't even get me started on their boneheaded decisions regarding the ES, RC, LS, and GS.
edit: OK I reread it, and it also mentions the transmission control unit. Hmm.
Last edited by arentz07; Oct 24, 2025 at 04:45 PM.
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Sad you can't trust Lexus anymore.











