stick shift

[cowboy]

I am thinking of replacing my pu as it is coming up on 200000miles and have been looking around for a cng pu it seems that most are auto trans I would think that range being such a problem that more of them would be ordered with a stick and overdrive but it looks like most are auto trans what gives it is starting to look like I am going to have to build it myself if anyone knows where one is 3/4 or 1 ton stick heavy springs ac crew cab large tanks at a good price and not to far from tennessee but will travel for right truck thanks

[CraziFuzzy]

Re: stick shift

Because of features like Lock-up, modern auto transmissions don't really rob the power that older ones do.. there is no significant mileage advantage to a standard transmission anymore, in fact, because of the electronically controlled nature of newer trans, they usually will end up in a better choice for gearing than a manual will. Plus, since most/all cng trucks were ordered by/for fleets, they are pretty much guaranteed to all be automatic.

[cowboy]

Re: stick shift

I cant agree with that because if they were not eating power you would not need a trans cooler. the heat came from the fuel tank and they cant stand real work as towing .I had a chevy with a turbo 400 before this one and put two trans in it before 200000 now granted I work my trucks but that is what I bought them for other wise I could buy one of those honda cars that curtis sells but it would look silly towing a backhoe and be hard to stop LOL

[larrycng]

Re: stick shift

Hey Cowboy, use a Smart for towing the backhoe.

I got 180,000 out of my E40D until I had it rebuilt when the wife fried the engine -- and about 90K of that was towing 10K 5th wheel. The rebuilder said I could have got another 40 to 50k out of it based on what was on the tranny.

If you are really worried about the automatic, put an Allison in the CNG Smart (FOTF -- rolling on the floor)

Later
Larrycng

[CraziFuzzy]

Re: stick shift

Auto trans DO require cooling, but that is mostly during accelleration, when it is running in slip. As soon as it locks up, there is no work going on with the fluid, and it behaves pretty much just like a manual, except it has a really good internal lubrication pump. Also, even if they ARE losing some energy, the magnitude, especially when looking at the larger trucks, is limited. EPA does not require mileage numbers for heavy-duties, and I'm not sure any company even makes a medium duty truck that has an available manual transmission. (Ford and GM do not, only 4 or 6 speed automatics).

[Wellarmed]

Re: stick shift

I agree with Crazyfuzzy, in that with the advent of the lockup converter, auto trans operating efficiency has greatly improved, but I will have to take Cowboys position that manual transmissions are more robust and still result in higher mileage then a similarly equiped automatic. I have looked at thousands of fuel economy figures of newly manufactured vehicles and have found that with few exceptions that Automatics do not provide the same fuel efficiency. All of the vehicles in my fleet are equiped with manual trannies, with the exception of my 68 GTO. And it is also on the chopping block to recieve a 6 spd manual trans. Although this discrepency between manual and auto is generally smaller now than 20 years ago it is still a concern when the overall totals of the US fleet are taken into account. This cumulative total will add up to thousands of barrels of oil a year. Part of the reason that the Auto is still not as efficient is that the Lock up converter is generally not coupled unless the vehicle is in a low load condition. Most manufacturers that produce an automatic overdrive trans (as well as most manuals) specifically state that towing is not to be performed in the overdrive gear, as it is the weakest gear in a transmission. If one follows that edict, then if they are towing with a 5 spd manual trans, they will be in 4th gear which will generally be a 1:1 ratio. If this is done with a manual trans your are effectively in lock up mode, but if this is done in an automatic, your Torque converter clutch will generally not be in lock up mode and therefore function as a previously non coupled transmission. I do find that autos are generally easier to operate in off road applications, but I personally do not feel that small benefit outweighs the negative aspects. By the way I have seen figures that showed having no overdrive at all, with a numerically lower gear ratio in the rear, has resulted in a 2% increase in fuel economy over the same operation with an overdrive trans. But you will need more gears to pull this off, to reduce the spread between gear changes.

[cnghal]

Re: stick shift

Cowboy,
That's why my Chevy 1 Ton Dually has a four speed with a "brownie", under/over unit. In low range (2:1) I can put out stumps. In high range empty, I have a great overdrive for mileage.
Plus, with 2 shifters and having to double clutch, most people are intimidated and don't want to borrow my truck.

[cowboy]

Re: stick shift

Cowboy,
That's why my Chevy 1 Ton Dually has a four speed with a "brownie", under/over unit. In low range (2:1) I can put out stumps. In high range empty, I have a great overdrive for mileage.
Plus, with 2 shifters and having to double clutch, most people are intimidated and don't want to borrow my truck.

twin sticks way cool

[CraziFuzzy]

Re: stick shift

Update to this thread... Last week I traded in my Crown Vic (as a clunker) and got a new VW Jetta TDI... It's got a DSG tranny (Dual Shift Gearbox) that really is the best of both worlds.. All the advantages of a manual (plus faster shift times), with all the smarts of electronic control and auto gear selection...

That, coupled with the turbo diesel, and I'm averaging 45mpg on the highway... cheaper to drive than my CNG CV was... faster too.. ;-)

[Wellarmed]

Re: stick shift

The turbo diesel that you bought is one nice little packege. I know many people that swear by them and few who swear at them. The European engineers are making US engineers look like they are asleep at the wheel. I will admit that I am personally biased towards stick shift, but I am reminded how much of a pain in the rear it is to have in the city of Riverside. Every time I drive down Victoria ave I am reminded why I do not need a gym membership. The City of Riverside really does need to be sued over their traffic control measures. Their solution to traffic control is to put a stop sign/light every two feet. This unnecessarily puts millions more Tons of pollutants into the atmosphere everyday,as it takes 6x more fuel to restart from a dead stop than if one were to drive with no obsticles. I mentioned this to Mayor Loverage once, but I could clearly see that it did not register in his cranium. I am sad to see your CNG vic get clunkerized. I hope someone can get usuable parts from it before it gets crushed!

[CraziFuzzy]

Re: stick shift

The turbo diesel that you bought is one nice little packege. I know many people that swear by them and few who swear at them. The European engineers are making US engineers look like they are asleep at the wheel. I will admit that I am personally biased towards stick shift, but I am reminded how much of a pain in the rear it is to have in the city of Riverside. Every time I drive down Victoria ave I am reminded why I do not need a gym membership. The City of Riverside really does need to be sued over their traffic control measures. Their solution to traffic control is to put a stop sign/light every two feet. This unnecessarily puts millions more Tons of pollutants into the atmosphere everyday,as it takes 6x more fuel to restart from a dead stop than if one were to drive with no obsticles. I mentioned this to Mayor Loverage once, but I could clearly see that it did not register in his cranium. I am sad to see your CNG vic get clunkerized. I hope someone can get usuable parts from it before it gets crushed!

It was showing its age.. and tanks only had 2 years left on them and the car would have been completely worthless. Got way more from the feds than I would have been able to sell it for, that's for sure. Besides, I like the irony of trading in a CNG vehicle to get a diesel... One that is cheaper to drive AND runs cleaner..

[larrycng]

Re: stick shift

Wellarmed, I think you will find that most pickups will be in lockup when towing in overdirve. I spend a lot of time in overdrive towing a 10K 5th wheel with no problem. You learn the vehicle shift points. I use a vacuum gauge and hold about 4 to 5 inHG. When I get down to 55 to 60 mph I shift back into direct drive. Usually the feed back system is in closed loop which will keep the AF ration close to stoichiometric giving you about the best fuel consumption for the situation. The old 460 and and E4OD will usually give in the mid 7's sans head winds.

I think most truck OD automatics will be locked until you get down into 2nd gear, even on a hard pull, then it will unlock (mine does it about 25 mph when not through detent) and that is when the tranny temp goes up. They will not lockup in 1st that I have found. As a side note, when you have a lock up converter and you take you foot off of the throttle you generally find that the converter will unlock. The converter will also unlock when you press the break pedal even with some TPS voltage that is above idle.

I believe I mention before, that in '76 GM did and MPG comparison with the Pontica Sun Fire; two vehicle the same except for the transmission and the rear axle ratio. Performance was about the same, but the AT picked up almost 2 mpg. This was from the GM Training Center in Burbank, Ca in late '76 when I was going through a 1 day AT class on the THM 200

Larrycng

[Curtis]

Re: stick shift

It was showing its age.. and tanks only had 2 years left on them and the car would have been completely worthless. Got way more from the feds than I would have been able to sell it for, that's for sure. Besides, I like the irony of trading in a CNG vehicle to get a diesel... One that is cheaper to drive AND runs cleaner..

Crazi- I need to check tha terms of service, but this abarrent behavior may require your banishment from cng-land.

Your savings on fuel sound reasonable, until the price of diesel returns to unreasonable. At $5.50 a gal you may see a slight shift in the economics, or at best, parity with cng.

[CraziFuzzy]

Re: stick shift

Crazi- I need to check tha terms of service, but this abarrent behavior may require your banishment from cng-land.

Your savings on fuel sound reasonable, until the price of diesel returns to unreasonable. At $5.50 a gal you may see a slight shift in the economics, or at best, parity with cng.

To be honest, fuel savings don't really mean much to me anymore, as neither I nor my wife routinely drive more than 15 miles from home. I'd gladly pay more per mile for this car over the Crown Vic anyways... besides.. we've still got te Expedition...

[cowboy]

Re: stick shift

Wellarmed, I think you will find that most pickups will be in lockup when towing in overdirve. I spend a lot of time in overdrive towing a 10K 5th wheel with no problem. You learn the vehicle shift points. I use a vacuum gauge and hold about 4 to 5 inHG. When I get down to 55 to 60 mph I shift back into direct drive. Usually the feed back system is in closed loop which will keep the AF ration close to stoichiometric giving you about the best fuel consumption for the situation. The old 460 and and E4OD will usually give in the mid 7's sans head winds.

I think most truck OD automatics will be locked until you get down into 2nd gear, even on a hard pull, then it will unlock (mine does it about 25 mph when not through detent) and that is when the tranny temp goes up. They will not lockup in 1st that I have found. As a side note, when you have a lock up converter and you take you foot off of the throttle you generally find that the converter will unlock. The converter will also unlock when you press the break pedal even with some TPS voltage that is above idle.

I believe I mention before, that in '76 GM did and MPG comparison with the Pontica Sun Fire; two vehicle the same except for the transmission and the rear axle ratio. Performance was about the same, but the AT picked up almost 2 mpg. This was from the GM Training Center in Burbank, Ca in late '76 when I was going through a 1 day AT class on the THM 200

Larrycng

I would think the increase was due to the axle ratio I would like to see the stick with the axle ratio from the auto we used to change big gms to strait shift and leave the tall rear and be in the mid 20s hwy we would use a 73 and later vega trans as the first gear is 3.22 to 1 to get rolling not bad for cars that got mid teens as built by gm