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Arl37 · 08-28-2016, 05:58 PM

When I got my truck it had a 700r4 and a 3:08 rear end. I installed a lockup switch and when I engaged lock up at highway speeds the RPMS would drop a couple of hundred to 2000 or just under.
I replaced the 3:08 with with a 3:78. Now when I engage the lock up at 65 the RPMS only drop a 100 to about 2300. Is this right?

08-28-2016, 05:58 PM	#1
Arl37 Registered User Join Date: Jul 2011 Location: Valley Center, Ca Posts: 277	Dont think my overdrive is working right When I got my truck it had a 700r4 and a 3:08 rear end. I installed a lockup switch and when I engaged lock up at highway speeds the RPMS would drop a couple of hundred to 2000 or just under. I replaced the 3:08 with with a 3:78. Now when I engage the lock up at 65 the RPMS only drop a 100 to about 2300. Is this right?