I drove sticks too but was forced to Auto when first Ford stopped making manual
Aerostars, (back then I towed a pop up, then stopped making them altogether. I
would have prefered a big engine Aerostar with a tow package and five speeds, and
just spring for a new clutch every few years. Instead I moved to an E150
conversion van.
Dan Weeks wrote:
> Well . . . it appears at lease ONE other person on this list likes sticks,
> and knows how to drive them. Should have figured it was you, Gerald! :-)
>
> Dan
> 75 Argosy 26
>
> > From: "Dr. Gerald N. Johnson, electrical engineer" <[EMAIL PROTECTED]>
> > Reply-To: [EMAIL PROTECTED]
> > Date: Sun, 28 Jan 2001 18:27:36 -0600
> > To: Multiple recipients of VACList <[EMAIL PROTECTED]>
> > Subject: [VAC] Re: Towing With A Manual 5Speed Transmission
> >
> > The tow truck that smokes clutches suffers from the factory quest for
> > economy and narrow range transmissions with excessively low rear axle
> > gear ratios. I've seen Ford trucks with that problem for nigh on 40
> > years. Even farm trucks.
> >
> > ANY engine needs to turn up to produce horsepower. Say 1500 RPM while
> > starting a load. Then the factory axle and first gear set that ground
> > speed too fast, the clutch has to be slipped to get the rig moving.
> > That's inherent in the automatic. The starting torque of the automatic
> > depends on a 3 to 3.5:1 low gear and a 2 to 2.5: 1 ratio in the torque
> > converter. Over all ratios 6 to 8.8:1. Attach that to a 4.10 rear axle
> > and you have an overall ratio of 24 to 35:1. Meaning that 1500 RPM at
> > the engine corresponds to about 1 to 1.5 revolution per second at the
> > axle. Ground speed 8 to 12 feet per second, 5 to 7 mph in round numbers
> > with 30 inch O.D. tires.
> >
> > Getting a 20:1 over all ratio with a manual transmission having a low
> > gear of 4.72 (ford 5 speed heavy duty) means the axle ratio has to be
> > 4.24
> >
> > Last winter I spent a lot of time looking at a smaller tow rig, F-150
> > with small V-8 and low gear in the manual transmission only 3.92. I
> > installed 4.10 axle gears. I'm quite happy with the arrangement, there's
> > enough torque in first gear to move my Caravel anywhere I want to move
> > it in first or reverse (though another 50% speed reduction would
> > occasionally be useful and lead to killing the engine less often while
> > trying for precision positioning), and enough torque in 3rd gear to get
> > up any hill in Missouri at 50 MPH. I toyed with going to 4.56 gears but
> > decided I didn't need the additional 1000 pounds starting capacity,
> > besides I could get there by change the rear tires from 29.1" OD to 25"
> > OD with really low profile 16" tires... A set of tires costs about what
> > the gear change did.
> >
> > Bigger loads require a higher rear axle ratio. I don't think the V10 low
> > speed torque will overcome the need for stump pulling torque for
> > starting with the 3.83 gears. With that much engine, I'd lean towards
> > 4.33 or higher.
> >
> > In my F-150, the gas mileage was 16 with the old 3.08 gears, and without
> > Caravel is till 16 with the 4.10 gears, providing I don't win too many
> > times at the stop lights. The Caravel (at 50 mph) dropped the mileage
> > down to about 15. Unhooking the air conditioning compressor raised the
> > unloaded mileage to 17.8. Running unloaded I generally start in second
> > gear because that's the same overall ratio NOW as the prior truck had in
> > second gear and that any truck normally has had starting with a 3 or
> > 3.5: 1 first gear.
> >
> > Be very careful about oversized tires, they can kill off the thrust
> > gained by high axle ratios.
> >
> > My neighbor has a 98 Dodge 3/4 ton 4X4 with a V-10 gas. It gets about 7
> > mpg empty or loaded (automatic transmission) and with a 32+ foot SOB
> > gets that same 7 whether towing at 50 or 70. I have yet to convince him
> > that his life is much shorter in emergencies at 70 when stopping and
> > control may be a severe problem.
> >
> > Buying a manual transmission truck these days is harder than buying a
> > Lamborghini or new Ford T-bird (sold out in 2 hours I heard). The
> > dealers don't want to touch them (their sales staff probably doesn't
> > know how to drive one to demonstrate it), and claims they can't sell a
> > used one. Several dealers I've visited plain out say, they won't have a
> > used manual transmission vehicle on their lot. If they take it in on
> > trade they will get rid of some other way than selling it on their lot.
> > I bought a '98 F-150 last January that I think had sat of the lot most
> > of a year because the claim was that the owner bought a new truck each
> > year. They were willing to sell it at a fairly decent price because of
> > that time on the lot. I answer the trade in question by pointing out my
> > current truck for trading is 14 years old, and my big truck is 35. (Hmm.
> > Maybe I should have traded them both?). As for transmission I point out
> > that I don't want to pay for the automatic, I don't want to pay for the
> > fuel to run the automatic and I don't want to pay for fixing the
> > automatic. Fixing and automatic is several times the cost of a clutch
> > even in a Ford which may destroy the clutch when the hydraulic clutch
> > cylinder fails and sprays the clutch plate with oil. I'd prefer a
> > mechanical push rod but they don't make 'em that way these days. I'd
> > prefer a NP-435 or Warner T-19 transmission with a 7.3:1 low gear too,
> > but that's not available to fit the modern truck.
> >
> > The stock 5 speed and stock (usually 3.08) gears are NOT suited for
> > towing. The highest ratio axle gears the factory installs are often not
> > very well suited for towing. I went to a hot rod shop that installs
> > gears of any ratio (in police cars too).
> >
> > I'd get bored with an automatic and frustrated when it shifted when I
> > didn't want it to shift. When the day comes that I can't be bothered
> > shifting gears, I probably shouldn't be driving but should have a
> > chauffeur handling the wheel chair anyway.
> >
> > Gerald J.
> >
> >
> >
> > To unsubscribe or to change to a daily Digest, please go to
> > http://www.airstream.net/vaclist/listoffice.html
> >
> > If replying back to this message, please delete all the unnecessary original
> > text from your reply.
> >
> >
> >
> >
>
> To unsubscribe or to change to a daily Digest, please go to
> http://www.airstream.net/vaclist/listoffice.html
>
> If replying back to this message, please delete all the unnecessary original
> text from your reply.
>
>
To unsubscribe or to change to a daily Digest, please go to
http://www.airstream.net/vaclist/listoffice.html
If replying back to this message, please delete all the unnecessary original
text from your reply.
