Mopar Action On-line – Tech Questions
Bob Mitchell, Jasper, TX, 1968 Dodge Charger 440
Richard, I enjoy your Tech Topics insights. Thank you forsharing your knowledge.My son and I have a couple 1968 Dodges. Mine is aCoronet and his a Charger. Both were originally small V8 engine vehicles butnow each has a 440 engine, 727 transmission and an 8 ¾ inch rear carrier(2881489) with 3.23 gears and a sure-grip differential. With gas pricescontinuing to rise we are looking for an economical way to increase our gasmileage. In lieu of purchasing an overdrive unit or a transmission swap webegan researching using more road friendly rear gears. We know 2.76 gearswere used with the 2070241 carriers in lower powered models in 1968 / 69 butcannot find such a gear set for the 2881489 carrier.We understand, ifperformed such a change will affect performance and require a speedo gearswap. We have no problem with either.In your learned opinion are we wastingcycles chasing this idea? If so, what do you suggest? Your attention to thisquery is very much appreciated. Bob Mitchell
The gearsets were made, and the idea is spot-on, taller axle ratios are #1on the “improved fuel economy” list. You’ll enjoy the cars more with thetaller gears, too, despite the marginally slower 60-foot times.
The only suggestion: Maybe keep and store the 3.23:1 centersections intact,and simply find complete used 2.76 pigs to drop in. They aren’t that hard tofind and are usually reasonably priced when you do. 742 carriers are alsoA-OK.