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**pjmoreland** · 06-17-2021, 08:48 PM

I ended up adjusting the low vacuum switch to 2inHg and the high to 9inHg. With this setup, it waits longer to lock the TCC in scenarios like accelerating onto the highway due to the higher high switch, but then once it finally locks the TCC, it stays locked longer under heavier load like from a gradual hill on the highway due to the lower low switch. Basically, it doesn't want to lock as easily, but once it does lock, it is more likely to stay locked. This is also good because it prevents the on/off cycling I was having when I had just one vacuum switch.

06-17-2021, 08:48 PM	#32
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,331	Re: 700R4 TCC Wiring I ended up adjusting the low vacuum switch to 2inHg and the high to 9inHg. With this setup, it waits longer to lock the TCC in scenarios like accelerating onto the highway due to the higher high switch, but then once it finally locks the TCC, it stays locked longer under heavier load like from a gradual hill on the highway due to the lower low switch. Basically, it doesn't want to lock as easily, but once it does lock, it is more likely to stay locked. This is also good because it prevents the on/off cycling I was having when I had just one vacuum switch.