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MPG....5-Speed vs 4-Speed

‘Clyde The Ride’ is an 06, first generation 2-wheel drive Tundra, with the 4.7 V8 and a 5-speed automatic.



While Clyde was in the shop: http://www…hp?t=11034



I rented my mechanics Tundra. Dex’s truck is an 02, first generation, with the 4.7 V8 and a 4-speed automatic.



Both trucks are Access Cab.



The shift points on the 5-speed are about 500 RPM apart; keeping to a shift point of 2,000 RPM, I go through all gears by 40 MPH.



The 4-speed has shift points about 1,000 RPM apart and will be in 3rd until I let way off, to be in 4th at 40 MPH.



Blasting up an on-ramp at warp speed, both trucks will hit 5,000 RPM and achieve 70 MPH by the merge (I prefer slowing if necessary) but the 5-speed is probably quicker and has more ‘go’ left when I merge.



Both cruise at a tad over 2,000 RPM at 65 MPH.



Both trucks were used for courier work in the San Francisco Bay area.



This involved trips from Concord to Vaccaville to Berkeley and back to Vaccaville as a highway run; some commute driving, freeway (65 MPH) and surface street driving (30-45 MPH)



Gas Mileage. 5-speed…Gas Mileage. 4-speed.



6-02… 382 mi… 18.1 mpg****** 6-18… 378 mi… 17.8 mpg

6-03… 247 mi… 19.2 mpg****** 6-19… 370 mi… 19.0 mpg

6-04… 213 mi… 20.8 mpg****** 6-21… 221 mi… 18.3 mpg

6-07… 396 mi… 18.2 mpg****** 6-23… 262 mi… 17.9 mpg

6-09… 242 mi… 17.3 mpg****** 6-24… 225 mi… 18.1 mpg

6-28… 403 mi… 16.6 mpg****** 6-26… 241 mi… 18.1 mpg

************************** 6-25… 290 mi… 18.3 mpg



Total Average… 18.4 mpg.***************** 18.2 mpg

Interesting. Is there a question being asked?

Nope.
Just a FYI.
Or your amusement.

Why do mags like Motor Trend and R/T include rpm figures at 60mph in top gear? We have debated endlessly about having the lowest RPM does not necessairly mean best mpg (I think it does though).

Same axle ratio?

I presume so, since the engine, tires, axle housing and other stuff and the fact that they run at the same RPM is the same.

Not a lot of difference. Considering the samples and their differences I would say the difference was within expected sampling error.

BTW good job on documenting and sampling.