why 4.10s

[turbo8765]

Originally Posted by joshp

Yeah this doesn't make sense to me, in the past the whole reason behind a 6th gear would be turning low rpm's on highway to get better mpg. 5th gear should be the towing gear on the highway I would think.

Also any news on a computer update for shift points? Mine seems like the transmission shifts and gears that it runs in are too tall at low speed putting too much of a load on the truck causing excessive fuel consumption at least that's what I figure. It's like you are at 30 mph and want to go faster the tranny doesn't shift it stays in the taller gear and you can feel the load on the engine which in turn is going to cause excess fuel consumption. Now the tranny will shift if you put your foot in it and maybe this is what I should do? Almost feels like being too easy on the pedal may actually cause worse mileage because it doesn't use the gears if you ease up in speed, instead it stays in the same gear.

Keeping the revs down is the key factor in reducing fuel consumption. This is why your truck is exhibiting the behavoir you've described.

More agressive gearing almost always equates to better accerleration. Exceptions, however, occur when traction is limiting or the gears are so short that the time spent performing additional gear changes exceeds the time saved with increased acceleration.

The likelihood is that the 4.10s represent an optimization of these two factors with respect to acceleration.

I haven't seen the gears side by side, but the 4.30's may also be larger and heavier. Do you know if this is the case?

[litfuse]

If anything, the 4.30s will be smaller and not as strong. And I don't know where guys are running at 2000rpms at 70mph with 4.10s. I run almost 80mph at 2000rpms in my rcsb sport package tundra.

[hotbox05]

Originally Posted by joshp

Yeah this doesn't make sense to me, in the past the whole reason behind a 6th gear would be turning low rpm's on highway to get better mpg. 5th gear should be the towing gear on the highway I would think.

Also any news on a computer update for shift points? Mine seems like the transmission shifts and gears that it runs in are too tall at low speed putting too much of a load on the truck causing excessive fuel consumption at least that's what I figure. It's like you are at 30 mph and want to go faster the tranny doesn't shift it stays in the taller gear and you can feel the load on the engine which in turn is going to cause excess fuel consumption. Now the tranny will shift if you put your foot in it and maybe this is what I should do? Almost feels like being too easy on the pedal may actually cause worse mileage because it doesn't use the gears if you ease up in speed, instead it stays in the same gear.

or just use the sequential

[POS71RS]

Hell, If they offered 3.90s, I would have gone with those.. bring my freeway cruise rpm down a touch...

[jkd]

It doesn't really matter, if you go to the specs you have double OD. 5th and 6th are both coming out of the trans at above 1:1 ratio. (Same as having a higher rear differential)

If anything, the 4.30s will be smaller and not as strong.

Not true at all. Regardless of any ratio in any rear end the physical size of the ring and pinion gears, brgs, etc are always the same.

[mhadden]

Originally Posted by jkd

Regardless of any ratio in any rear end the physical size of the ring and pinion gears, brgs, etc are always the same.

Except in the case of the Tundra where the 4.3 rear end is a 10.5" diameter gear and the 4.1 is a 9.5".

[TRDSucker]

Originally Posted by litfuse

I still think it is strange for toyota to make two individual ring and pinion ratios. I would imagine it would have been cheaper for toyota just to make all their axles with 4.30s. There has to be a reason why Toyota did the 4.10s, besides just gas mileage, because I don't believe there is any substantial difference between the 4.10s and the 4.30s. I would think if they were worried about gas mileage they would have thrown in some 3.73s.

IF you think that is a waste, then consider that GM has at least 4 ratios available in the 1500 ld. Ford at one time, had about six for the f-150, ranging from a 2.-- to 4.30 or something like that. I would have though that they would have spaced out the option a little more though. I like that the 4.30's make my 4.7 feel like it is on anabolics though.