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'98 SC400 Transmission Pressure adjustment

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Old 06-11-07, 01:04 PM
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Devir
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Default '98 SC400 Transmission Pressure adjustment

searched... many times...

I have myself a 98 SC400 with that beautiful 5 speed (slow shiftin) Auto.

does the line tightening method to boost fluid pressure work for the 98 models? If so, where would I find the line to adjust?

Pictures would be wonderful as they truely do speak 1000 words.
Old 06-11-07, 03:27 PM
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mitsuguy
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it's internal to the trans... you have to drop the pan and remove the filter...

I would assume it works the same on your car, but I would hate to say one way or another...
Old 06-12-07, 08:20 AM
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Devir
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THat's a bummer to hear. I know in some older cars, it's a simple tension adjustment under the hood. The line looks similar to the fuel line, and when adjusted would raise the transmission oil pressure for faster harder shifts.

Dropping the pan would be the install of a Shift kit. That is what I would also like to do in the future. I dont know where to purchase a shift kit and the search term is too short... (4 or more letter words). The only place I know that sells them is in Australia, and there's no website or order forms that I know of.
Old 06-12-07, 11:54 AM
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sc250tt
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if its anything like the older sc's all you might have to do is drop the pan and turn the pressure up on the valve body
Old 06-12-07, 12:04 PM
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mitsuguy
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Originally Posted by Devir
THat's a bummer to hear. I know in some older cars, it's a simple tension adjustment under the hood. The line looks similar to the fuel line, and when adjusted would raise the transmission oil pressure for faster harder shifts.

Dropping the pan would be the install of a Shift kit. That is what I would also like to do in the future. I dont know where to purchase a shift kit and the search term is too short... (4 or more letter words). The only place I know that sells them is in Australia, and there's no website or order forms that I know of.
unfortunately, definitely not like that.... HOWEVER... assuming it's similar to the 4 speed autos, here's a writeup which includes a DIY shift kit install:

http://www.supraforums.com/forum/sho...d.php?t=267655
Old 06-12-07, 02:10 PM
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here's another, more fitted to our cars (updated)

http://jkwebdesign.net/lsocbb/viewtopic.php?t=1915
Old 06-12-07, 04:13 PM
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MJHSC400
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Adjusting the cable on the old style (92) really sped up shifts for mine-- And it holds a gear better --
Old 06-13-07, 06:34 AM
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Devir
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Thanks for the links and information.

Eventually I'll get a shift kit, once I find one.
Old 01-11-17, 03:59 PM
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Devir, there is a link I found and someone did it to their SC430 with the same A650E trans equipped, it's as simple as dropping the transmission oil pan and using a flathead screw driver and pushing it in and turning it clockwise. I'll post a picture of what needs to be adjusted. I did the adjustment on my 98 sc400 and the shifts are much more firm and quicker and it took the delay out
Old 01-11-17, 04:15 PM
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gerrb
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You know that you have just bumped a thread that is more than 9 years old and you are talking to Devir who hasn't logged into this forum in 6 years
Old 01-11-17, 04:16 PM
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Originally Posted by bboyjohn04
Devir, there is a link I found and someone did it to their SC430 with the same A650E trans equipped, it's as simple as dropping the transmission oil pan and using a flathead screw driver and pushing it in and turning it clockwise. I'll post a picture of what needs to be adjusted. I did the adjustment on my 98 sc400 and the shifts are much more firm and quicker and it took the delay out
There are 3 settings, 1st dial is factory setting for super smooth shift and i hear the the gs400 comes set at 2nd dial, i bump mine up to the 3rd dial.
This was after i made the adjustments. Remember its not 3 full turns, you push the tab in and turn it to the 3rd dial
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Old 01-12-17, 07:30 PM
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i will attempt this
Old 01-12-17, 10:15 PM
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The tranny fluid was pretty nasty in my '98 when I bought it, so I did this mod at the same time as a good excuse to do a more thorough drain than just opening the plug. If there was any resulting performance difference, it was too minor to be sure.

Here's a more detailed thread for people wanting to try it: https://www.clublexus.com/forums/per...ting-dial.html
Old 01-16-17, 04:25 PM
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it's worth it, I've been driving around like this for a year now, the shifts feels very good and pulls hard into the next gear, the idea of it is to also save the life of the clutch packs so it takes away the delay and it helps from keeping the trans from creating too much heat

here's the original thread, its a good read for anyone who has the auto 5sp A650E, goes for 98+gs300/gs400/ls400/sc400/ and is300. i'll share a video

https://www.clublexus.com/forums/sc4...0-a-650-e.html
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