So I've been researching and it seems as though the Lexus IS300/IS350 front upper control arms may be the same as the LS430. Both front upper arms use part # 48610/48630

Picture 1: LS430 front suspension



Picture 2: IS350 front suspension



Picture 3: IS300 front suspension



So if this is true, that should mean that adjustable upper arms are cross compatible. This also should mean the SPC adjustable ball joint will work as well.

 

Son of a.... I knew I should have removed the Cusco FUCA's from my old IS300. Dammit!

If I can find the old stock IS300 arms, i'll see if they swap out or not. I have no idea if I still have them though.


Also, if memory serves, the SPC ball joints were a no-go for me when I was looking into those or adjustable FUCA's as they effectively raise the FUCA higher due to being thicker than stock, which in turn makes you more susceptible to FUCA and strut tower contact. Anyone with a slammed IS/GS/LS is familiar with ramming the RUCA's into the strut towers. lol

 

I think I may pick up a set of adjustable FUCA's at the local distributor tomorrow and confirm if they will work.

 

That would be both awesome and sucky if they are the same seeing as I am having adjustables fabricated right now.

 

this is intriguing. My only fear with the megan/cusco/godspeed arms out there is that when really low, the upper strut tower will need to be cut out a lot more.

Let us know how they are, and how much adjustment there is!

EDIT:

GS300 also utilizes the same front upper control arms, #48610/48630

SC300 also uses the same part number for rear upper, however they look different when comparing the two.

 

Hold on a minute. The five digit code in the picture is basically just the numeric "part name". Thus the right hand control arm part name is 48610G. An SC, LS or IS upper control arm is 48610. This doesn't mean that they're interchangeable or the same thing. The complete part number is different for an LS right hand control arm is 90173‑10012 and an IS is 48610‑59025 and an SC is 48610‑39085. All are very different parts.

 

We're talking about LS and IS, not SC.

LS430 - 48610-59035 - ARM ASSY, FRONT SUSPENSION UPPER, RH
ISx50 - 48610-59065 - ARM ASSY, FRONT SUSPENSION UPPER, RH
IS300 - 48610-59025 - ARM ASSY, FRONT SUSPENSION UPPER, RH

So all parts #'s are slightly different. I know for sure that the IS300 upper arms will work on the ISx50. It's not an exact part # match, but that doesn't mean it won't work.

 

I used the SC just as an example. If the full part number is different then the part number is different. Some holes and/or dimensions MAY be the same but similar part numbers don't mean anything.

 

Ok good because I was worried I was wasting my time and money haha

 

Gen1 and Gen2 IS uppers are NOT compatible. Different ball joint tapers. Not sure on the LS.

 

ftw just rock nagisa's or 326power...

 

Doesn't 326 power only make demon camber arms?

 

Just go with Nagisa.... It's expensive but you know it's proven. I've been running Nagisa FUCA and RUCA and Toe arms without any issues or worries. Sometimes you really just have to pay to play, no getting around it.

 

pretty much sum it up...

 

Yeah I'll just get Nagisas or maybe the Moonface arms. Too much effort just to save a few bucks.