You have something that is great for what it was designed for, but the problem is your are trying to use it differently than it's design purpose. Granny gear, which BTW, lots of people would consider swapping their first born for, (just kidding) is not supposed to be used for regular driving. In a hwy application it is designed to start a very heavy load moving so that your regular street gears can take over and pull the load. In off roading is is used for a different purpose, but just as important - going SLOW. If you really want to get the best use out of your tranny, set it up for 2 through high for the concrete, and leave 1st or granny for what it was designed for. Do not figure it into your "take off from a stop light" type driving. Don't know what type of tranny you have, but there are basically 3 different styles:
1) 1st through high for all driving. High being direct 1:1
2) 2nd through high for all driving. 1st being a granny for starting heavy loads.
3) 2nd through direct (1:1 ratio) plus overdrive. 1st being a granny gear and the highest gear being an overdrive, less than 1:1. This is the most versatile transmission. A very low, seldom used gear for starting heavy loads and a final high gear that is only used on the highway at speeds of 35/45 and up.
Sounds like you have a #2 type transmission (my own numbers). This transmission was designed for delivery type use where heavier loads are frequent and short NON highway trips are the norm. A farm truck, delivery truck, lower speed heavier hauling type truck. You can change the tire size and/or change the axle gears and move this truck into a different catagory, but it really will not fit there comfortably. Granny gear is often non syncrornized. It usually has heavy springs to keep you from shifting into it accidently. Yes, it can be set up so that it is a usable drive gear, but look at the ratio differences between the gears. The first drive gear is usually in the 3.xx range, 2nd in the 2.xx range, 3rd in the 2.xx to high 1.xx range, but the granny is usually a 5.xx or 6.xx gear. Look at the gap between it and the next gear. It isn't designed for regular use.
Hope this helps.
Doug '97 TJ
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