2nd Gen Non-Engine/Transmission mileage/ 4.10 gears

[SRehberg]

I just returned from a 1,000 mile solo trip to Southern Calif. , with my '96. This is the first time I have been able to check the mileage since I bought it, so wanted to know if I'm in the park. It's an auto with 2wd, CCab, bone stock, lightly loaded (suitcases, two people, one dog) and typical weather conds. My other '96 I had with the 3. 54 gears (same other things) would crank out 23mpg at 70mph. on the same trip, time after time. This time, with the 4. 10's, a solid 19 is the best she'll do. I expected a couple of mpg, but should it be down 4mpg? I drove 67mph, with a few passing times at 70. Thanks.

 

[dpuckett]

That sounds about on the lower side of normal. With the 4. 10s and the P7100, you are above your best BSFC curve. I have gotten as high as 22 at the same speed in my 91; non intercooled, 4. 10, 5 spd, but it is probably 2000# lighter than yours. One guy up in Platteville, CO told me a few years ago that the cat sometimes will cause a little back pressure after a few years/ miles, and removing it might net you a little gain. While you're at it, pitch the muffler, too. I'm looking for a set of 3. 07s or an OD unit for mine, but they are a little ways off, monay wise.



Daniel

 

[ndurbin]

bump up the timing and it'll help some too. if it hasn't ever been done it's probably slipped.

 

[jtwcummins]

For almost seven years of ownership



13. 6 in town

19 hiway staying at 2k rpm

75 mph on hiway gets about 18. 5

 

[TGaines]

I have a 96' with auto and 4. 10's and I get about 16 in town and on the highway. I averaged between 10 adn 12 pulling about 7000 lbs up the Alcan this summer. I was thinking of swapping in 3. 73's just for some improvement in mileage. I do have 235's on my truck, so that may be some of the difference. Not sure.

 

[dremelts]

Daily driving to/from work, 50 mi. round trip, 70% expressway - I get 18. 5. (Might actually be slightly better than that as I have 265 tires instead of stock 245s which makes the odometer read a little less than actual. )

 

[Dkevdog]

Originally posted by SRehberg

. This time, with the 4. 10's, a solid 19 is the best she'll do. I expected a couple of mpg, but should it be down 4mpg? I drove 67mph, with a few passing times at 70. Thanks.

Welcome to my world. . Sounds about right, although I have seen as high as 20. 5.



Kev

 

[LHartman]

With my 4:10's, I'll be lucky to get 17 on the hwy. I get a solid 14 in town

 

[SRehberg]

I want to thank everyone for the replies. It looks like the 19mpg is about what to expect. I just bought this truck about 1 1/2 mos. ago, so this was my first opportunity to check mileage. I'm hoping it makes pulling my 5th wheel a little easier than the 3. 54's would. It weighs (according to the mfg) about 8800lb fully loaded. I know the mfg's tend to be on the low side, so this is all I have to go by; I haven't been to a public scale yet.