Double clutching from 1st to 2nd

[tom'sB2B]

I've been driving my 1947 D24 a little more now. Try ing to sort out the squeeks and rattles after the rebuild. I keep grinding it from 1st into second. I figured it needed a linkage adjustment, but I have found if I double clutch it doesn't grind. Is this normal? I know it's necessary when down shifting. Very curious.

I don't have this problem in my 1950 B2B.

Any thoughts?

[kencombs]

Not normal.  Usually due to either being in need of a clutch adjustment or worn synchronizer rings in the trans itself.

[plymouthcranbrook]

Try shifting very slowly into second. That works when my 52 is balky going into second.Pause in neutral with the clutch in to allow gears to mesh speeds. 

[casper50]

My D24 likes to do a little grind from 2nd to 3rd.  Almost everytime.

[maok]

What is your oil level in the gearbox?

[Bbdakota]

Just for comparison, my d24 has no grinding 2 to 3. The only grind I get is if I put it in 1st to soon after depressing clutch. So I don't think it's normal, like has been stated, check clutch adjustment, if that's good, probably worn synchro. 

[kencombs]

13 hours ago, maok said:

What is your oil level in the gearbox?

Good point.  It's also possible that the wrong oil is in it.  In colder temps, heavy oil can cause that.  Conversely, lighter than normal viscosity can effect the way the sychros work.    Manual trans have been recommended to use everything from 140 to ATF, depending on design, usage and temp.  My planned A833 uses ATF!

[RobertKB]

15 hours ago, plymouthcranbrook said:

Try shifting very slowly into second. That works when my 52 is balky going into second.Pause in neutral with the clutch in to allow gears to mesh speeds. 

 

Like he said. I have to do this with my 100,000+ mile '53 Plymouth. It's like it going into third as well. I've run this car like this for 30,000 miles and the tranny has never got worse. Syncro gears wear but a little TLC shifting really helps.

[greg g]

Make sure you clutch is disengaging completely when the pedal is pushed in.  If it is dragging slightly it will allow the input shaft to spin enough to keep the synchros from working to stop it during the shift.  Try extending the linkage going to the throw out bearing fork slightly and see if it corrects.

[MarkAubuchon]

agree with everything already described. I do know there is a fine line .  On my 49, I just replaced the synchronizers and it will still grind going from neutral to first. I find that if I shift into second with the clutch depressed and then into first no grinding.  moving first to second, clutch needs to be fully depressed no grinding.  Probably need more fine tuning.

[kencombs]

1 hour ago, MarkAubuchon said:

agree with everything already described. I do know there is a fine line .  On my 49, I just replaced the synchronizers and it will still grind going from neutral to first. I find that if I shift into second with the clutch depressed and then into first no grinding.  moving first to second, clutch needs to be fully depressed no grinding.  Probably need more fine tuning.

That is perfectly normal.  When the clutch is depressed while running in neutral, the gears are all turning. Since there are no synchronizers on first and reverse, you have to wait for the rotation to stop before shifting, or stop it using the second gear sychro as you are doing.

Temperature and oil weight has some bearing on how long that wait might be.  Light oils let the gears spin longer,  cold temps stop them quicker.

Edited June 24, 2019 by kencombs

[plymouthcranbrook]

Another thing I did on my 52 that helped shifting was to go under the hood and clean the linkage where it attached to the steering  column. 60 years of road grime and dried grease gummed up the movement. I scraped and used BrakeKleen to remove it and then sprayed WD40 all over the thing. Really made shifting smoother.

[Don Coatney]

I assume your 1947 D-24 is a fluid drive car. Why do you use 1st gear and why do you use the clutch? In my D-24 fluid drive car I back out of the garage and use the clutch to shift to 2nd gear. That is the last time I use the clutch. I easily accelerate from a dead stop in 2nd gear without using the clutch. When it is time to shift to 3rd gear I drop the lever to neutral and put a slight downward pressure on the shift lever and it slips into 3rd without grinding. When I come to a stop light I move the shift lever to neutral and put a slight pressure upward to the 2nd gear  and when the slow down speed is correct it pops into 2nd gear without grinding and without using the clutch. I hold the brake until the light turns green then hit the gas and repeat the above procedure. 

[dpollo]

these  transmissions  often do not enjoy Hypoid lubricants as needed in the differential,   try a non hypoid gear oil  maybe SAE 80 before you tear into things.

 

DodgeB4ya on this forum can advise you better than me on oils.

[Polsonator2]

I experimented with all kinds of gear lube, from tractor supply's ford tractor transmission (sae 90) to royal purple 75w 90 and 75w 140.  The one that works best for me is an sae 140 gl4 from oreilly.  My synchros would grind occassionally with the royal purple if I shifted too fast from 1st to 2nd or 2nd to 3rd and the tractor supply ford transmission gear oil was so so.  I also tried the oreilly 85w 140 but the sae 140 works way better.  I can now shift as fast as I want with no issues and the synchros feel smooth.  Shifting to 1st gear at a stop is smoother now too.  My manual for my '39 says use sae 160 or sae 140 in my 3 speed.

 

https://www.oreillyauto.com/shop/b/chemicals---fluids-16461/grease---lube-16582/gear-oil---additives-16905/gear-oil---140w-20063/754ba5cbea99

Edited July 22, 2019 by Polsonator2

[rallyace]

Be careful with your lube choices. Anything with a spec newer than GL-1 has additives (mostly sulfur compounds) that are not good for the 'yellow metals' (brass and bronze) that are used our three speed transmissions.

[Polsonator2]

Here is an interesting article about the yellow metals issue: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.widman.biz/uploads/Transaxle_oil.pdf&ved=2ahUKEwj6oZib0MnjAhUnGTQIHdUiBsEQFjALegQICBAB&usg=AOvVaw1neW6ilOnAwS-CfNyPIeiR

[TodFitch]

1 hour ago, Polsonator2 said:

Here is an interesting article about the yellow metals issue: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.widman.biz/uploads/Transaxle_oil.pdf&ved=2ahUKEwj6oZib0MnjAhUnGTQIHdUiBsEQFjALegQICBAB&usg=AOvVaw1neW6ilOnAwS-CfNyPIeiR

 

Here is a shorter URL to that article that is stripped of the Google tracking code: https://www.widman.biz/uploads/Transaxle_oil.pdf

[Don Coatney]

On 6/25/2019 at 1:54 PM, Don Coatney said:

I assume your 1947 D-24 is a fluid drive car. Why do you use 1st gear and why do you use the clutch? In my D-24 fluid drive car I back out of the garage and use the clutch to shift to 2nd gear. That is the last time I use the clutch. I easily accelerate from a dead stop in 2nd gear without using the clutch. When it is time to shift to 3rd gear I drop the lever to neutral and put a slight downward pressure on the shift lever and it slips into 3rd without grinding. When I come to a stop light I move the shift lever to neutral and put a slight pressure upward to the 2nd gear  and when the slow down speed is correct it pops into 2nd gear without grinding and without using the clutch. I hold the brake until the light turns green then hit the gas and repeat the above procedure. 

 

 

Broke my car out of storage today. Pulled out of the storage unit in 2nd gear and shifted to 3rd when the speed was right. Never left 3rd gear all the way home. stopped for 8 red lights and 2 stop signs. Never used the clutch. Easily kept up with the speed of traffic.

 

The car had not been started sense January 21st. Had to use a 12 volt battery pack my son borrowed from work and it fired off directly. The 6 volt alternator went to work and the oil pressure and temperature came right up. Once I knock the dust off of her she will be good go.