Rear differential question

finaltable · 11-12-2007, 10:11 PM

I am looking for ways to improve the fuel efficiency of my '90 NA. The code on my door sticker (G282) says my rear end is an open 4.3 ratio. I understand that 3.9 and 3.7 ratios were also available. What difference would I see if I switched to a 3.9 or 3.7 and is this something that would require replacing the whole differential or could they just open up my existing one and replace gears?

11-12-2007, 10:11 PM	#1
finaltable 3" Exhaust Join Date: Sep 2006 Location: Texas Gulf Coast Posts: 99	Rear differential question I am looking for ways to improve the fuel efficiency of my '90 NA. The code on my door sticker (G282) says my rear end is an open 4.3 ratio. I understand that 3.9 and 3.7 ratios were also available. What difference would I see if I switched to a 3.9 or 3.7 and is this something that would require replacing the whole differential or could they just open up my existing one and replace gears? __________________ Current ride: Not a Supra :-(