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fourspeedwagon · 06-04-2013, 02:12 PM

TJ- First, you should crawl under the truck and see what trans it has. If you only detect one shift and it tops out at 65, you may not be engaging 3rd gear. Does it have a tachometer? rpm and mph, along with tire size and we can figure out what the rearend gear ratio is. If it has extraordinarily low gears, then a swap would be the way to go, if it's running around on the interstate in second gear then we can start to chase why.
Note the shape of the trans pan and number of bolts or post a pic of the pan and we can help. Greg

06-04-2013, 02:12 PM	#4
fourspeedwagon Registered User Join Date: Oct 2010 Location: Yakima Valley, Washington Posts: 580	Re: Gas Mileage/ Top End Speed for 72 C20 TJ- First, you should crawl under the truck and see what trans it has. If you only detect one shift and it tops out at 65, you may not be engaging 3rd gear. Does it have a tachometer? rpm and mph, along with tire size and we can figure out what the rearend gear ratio is. If it has extraordinarily low gears, then a swap would be the way to go, if it's running around on the interstate in second gear then we can start to chase why. Note the shape of the trans pan and number of bolts or post a pic of the pan and we can help. Greg