clutchless shifting?

[hot rod deuce]

I would say you guys wacked that one square on the head!!
Ever try and "limited slip" additive in the synco boxes?

You know, one thing that really grinds my gears is when people say it is hard on a non-syncro to use a clutch! Unless you have some one show you that really really knows it and you understand how the thing works just use the dang clutch. Think of it as less time on the stair stepper at the gym!

I know it can be done and I do it from time to time but too many times they will not get it in gear 100% of the way with a big load on a hill.....BAG.

Had a brand spankin new 18 speed in a Freightliner heavy haul rig and after one guy drove it for a day it was junk. So now i just tell them what the eaton book says, Always double clutch during gear changes, range changes and split shifting.

 

[Capt.Marion]

by clutching, I assume you mean double-clutching? I thought the deuce didn't have synchromesh...

 

[SasquatchSanta]

This may be crazy but would it be possible "and feasible" to split between 4th and 5th gear by using the transfer case?

It seems like I read about someone that was using the TC to split 4th and 5th --- much like a Mack Duplex.

I'm going to weld an extension onto my transfer case shifter and also change the angle of the lengthened shifter by heating and bending so the modified shifter handle is positioned so I can rest my leg against it on long trips. Modified in this configuration, the shifter would be easily accessible for on the fly shifting BUT, I am concerned about blowing up a transfer case.

I grew up drift shifting (without a clutch) non-syncro transmissions but I'm spooked about reaching into the transfer case at 40 MPH.

 

[wyliek]

whats the advantage of double clutching, if your just waiting for the synchros to catch up, why cant you just hold the clutch in and wait longer between shifts??
wylie

 

[devilman96]

Be mindful of how you modify the TC's shift linkages and don't rest your leg, hand or anything else on it. First comes the slop in the linkage, then comes the slop in the shift rods detent ball and spring, then ya cant keep it in high anymore, then comes the slop in your shift forks from trying to use a bungee cord to keep it in gear... then your driving across country and you loose high all together *snicker* then ya drive from KY to TX in low cause its all you have left *snort*.... then your here asking do I rebuild or do I buy a used TC...

Remember when your doing PM work on your truck, adjust the nut tensions on your shift levers at the swivel points (TC and PTO) so they don't bounce and bob all over the place when driving... Helps save wear and tear on the detents, shafts, seals, etc...

 

[DDoyle]

by clutching, I assume you mean double-clutching? I thought the deuce didn't have synchromesh...

Ah, all the G-742 vehicles (M35, etc) DO have a synchromesh transmission, overdrive 5 in Multifuels, direct 5 in gassers.

Regards,
David Doyle

 

[mangus580]

 

[jh1990]

yea my dad (ah1955) double clutches just about everything from my moms little mazda to our deuce, I can't remember if he double-clutched his tractors when he still drove, I think he did sometimes and other times he didn't us the clutch at all, but he's an old school truck driver and he did it for almost 30 years so I think he knows what he's doing. I wish he would let me drive our deuce a little more then once ever.

 

[Stan]

Since shifting is being discussed, somewhere in a manual covering the M35 it states to ALWAYS start in first gear. Anyone else seen this. Starting in second on flat ground doesn't seem to lug the engine.What do you do?

 

[rdixiemiller]

The reason for the "start in first gear" rule dates back to the old sprag transfer cases. 1st and reverse actuate the sprag shift rod to select the correct sprag set.
1st gear eliminates lugging on hills. I seldom use first on level ground, just ease out in second. I used to drive a worn out IHC dumper that we shifted without the clutch, but I prefer to use the clutch on anything that I can.

 

[houdel]

I grew up on manual transmissions, back in the day when you had a restriction on your driver's license if you took your driving test in an automatic!

That said, I am not all that excited about double clutching, unless you have a vehicle with a non synchromesh tranny, then you HAVE to double clutch! Been there, done that. But I don't see much practical purpose in double clutching a synchro tranny. Take your time moving the shift lever and let your synchros do their job, that is why the danged things were put in your tranny in the first place! Unless you KNOW exactly what you are doing, you will probably do more harm than good trying to double clutch a synchro tranny!

As for starting in first gear, I HAVE to do it all the time in my Deuce. I have one of those oddball English Spicer 3053 trannys in my Deuce. NOT 3053A, not 3053B, just plain old 3053. I think is has a higher OD than the usual 3053A because I can cruise an HONEST 55 MPH (verified with my GPS) and I'm only turning 2100-2200 rpm. I just can't start it moving in 2nd gear, takes way too much clutch slippage for me!

And as for split shifting the transfer case, I do it all the time. When I'm in a tight spot, like the grocery store parking lot, I put the xfer in low range to make manouvering easier. When I get it out on the road, I go up through the gears in low range. When I'm wound up in 5-low, I put the clutch in, shift the tranny back down to 4th, pull the xfer into high range, and then run up through 4-high and 5-high just like normal.

The transfer case was designed with synchros to allow it to be shifted on the go it tactical situations.

 

[SasquatchSanta]

Hello Devilman.

I've rebuilt several M37 transmissions and transfer cases but I've never been inside an M35 TC. I was under the impression that the M35 TC shift lever pivited back and forth inside a ridgid slot (casting) and therefore side thrust would not cause the problems you mentioned --- thanks for the insight.

Hey Lee,

That's a neat trick on splitting 4th. I also sometimes use low range as you mentioned but hadn't figured out how to get back on the top deck without stopping dead cold.

I was really surprised to learn that shifting without the clutch is hard on syncronizers. I've been doing it for years on just about everything I've ever owned and never had a problem. As you know, when you do it right the transmission literally "falls" in gear. I taught my daughter how to shift w/o the clutch when she was learning to drive --- she used to freak our her friends when she did it --- especially the guys. I guess I had better tell her to stop before she does serious damage to her new Saab. (I hate that car --- if is was't daughters pride and joy I'd run over it with the deuce).

 

[houdel]

Ernie - I don't disagree with you at all. You are right, clutchless shifting can be done IF you know what you are doing. Same with double clutching, necessary on a non synchro truck IF you know how to do it, of dubious value on a synchro vehicle. I've done both when I had to (blown clutch on my Camaro, non-synchro FD Water tanker). My point is, most of the current generation have grown up with either auto or full synchro trannys, and have never learned the proper techniques for clutchless or double clutch shifting. They are skills which need to be learned PROPERLY. The vast majority of drivers are better off single clutching a manual tranny and letting the synchros do what they are designed to do.

 

[devilman96]

Ernie,

Its not side load its up and down or forward and back... If your gonna rest something up against it its gonna bounce. You can see the linkage in the pic below. What happens (in theory) is a load, or bouncing around to much from slop in the linkage wears out the detent spring from pulling and pushing the shift rod... Detent failure in these TC's is common, personally I think the shift handle is a bit long to begin with and shortening it would proably help, less leverage, less weight, less bouncing.

Once they wear out people tend to use a bungee to hold the TC in high, yes it will drive but the constant force on the fork eats the fork legs up until they fold or pop past the gear leaving you with no high range.

My suggestion is to snug up the 2 bolts shown in the picture (and / or shim them) periodically to help keep the handle from flopping around.

 

[SasquatchSanta]

Hello Devilman 96,

Thanks for articulating on this subject. You've certainly sold me --- I'm glad this subject came up before I modified the TC shifter. I guess if I need a leg rest I'll have to build one.

I've got an M37 transfer case out in the garage that I rebuilt several years ago and immediately took back out of the truck because it wouldn't stay in gear. Everything looked fine shifter fork wise but the damned thing wouldn't stay in gear. I've thought about opening it back up in an attempt to see what went wrong. The forks looked good ---maybe it's the shafts. Thks for the insight.