The Ford Barn

anteek · 09-12-2014, 05:33 PM

I have a '40 mercury rear that I'd like to use in a '36 ford. I was told the merc has the pinion gear permanently attached to the driveshaft. Was it welded to it or removeable? How can I use this 3.54 in a shorter wheelbase car?

rotorwrench · 09-12-2014, 06:21 PM

The shaft is a part of the pinion and is not removeable unless it is cut. Depending on the diameter of the shaft, it may be possible to remove the long shaft portion and have a machine shop cut some splines back into it to mach a standard Ford 6-spline pinion. I've never tried it but it could be worth looking into with the price of the new ring & pinion gear sets. it may not be large enough for 10-spline though but I just don't know without comparison

Karl Wolf · 09-12-2014, 07:12 PM

The machine shops I contacted all wanted a lot of cash to cut splines onto the shortened shaft...

Except for Mitchell Overdrive. I would contact them. I was told that they set up to do the spline cutting operation once in a while- you may have to be patient...

I found it comforting that they do this as a regular practice.

Karl

jailhousebob · 09-12-2014, 09:08 PM

I've done several sets,always 6 spline,and it works out great.Plus the orig ford/merc gears are superior the the aftermarket stuff . My guy gets $150.00 to spline the pinion stub .Bob

supereal · 09-12-2014, 11:12 PM

When we adapt an early driveshaft to a later pinion, we use an adapter. We cut the shaft in our long bed lathe, then turn the adapter to a slip fit. The whole assembly is chucked in the lathe, then welded. Cutting splines is a very complicated and expensive job, so using the adapter makes less cost, and a quick turnaround.

GEOFFNZ · 09-13-2014, 01:19 AM

Sponsored Links (Register now to hide all advertisements)

We have a 39 Mercury3.54 gearset running in 36 housing.The pinion was cut off with a short shaft and splined to 6 splines.Works very well.Cheers.

Fred A · 09-13-2014, 12:17 PM

Hard to imagine that machine work and other handling expenses could be a better idea than buying aftermarket gears. Declaring that the original gears could be superior seems like a shoot from the hip opinion, difficult to prove. 3.54 gears are no longer a premium item. Many guys are finding that 3.27s make great road gears where other gearing and torque producing issues are addressed. I does however sound like a great boast to make over the bench. Good Luck: Fred A

Cecil/WV · 09-13-2014, 04:20 PM

I have a Merc rear that is surplus.

09-12-2014, 05:33 PM	#1
anteek Senior Member Join Date: Apr 2011 Posts: 319	'40 merc pinion question I have a '40 mercury rear that I'd like to use in a '36 ford. I was told the merc has the pinion gear permanently attached to the driveshaft. Was it welded to it or removeable? How can I use this 3.54 in a shorter wheelbase car?

09-12-2014, 06:21 PM	#2
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	Re: '40 merc pinion question The shaft is a part of the pinion and is not removeable unless it is cut. Depending on the diameter of the shaft, it may be possible to remove the long shaft portion and have a machine shop cut some splines back into it to mach a standard Ford 6-spline pinion. I've never tried it but it could be worth looking into with the price of the new ring & pinion gear sets. it may not be large enough for 10-spline though but I just don't know without comparison

09-12-2014, 07:12 PM	#3
Karl Wolf Senior Member Join Date: May 2010 Location: Mill Valley,Ca. Posts: 1,509	Re: '40 merc pinion question The machine shops I contacted all wanted a lot of cash to cut splines onto the shortened shaft... Except for Mitchell Overdrive. I would contact them. I was told that they set up to do the spline cutting operation once in a while- you may have to be patient... I found it comforting that they do this as a regular practice. Karl

09-12-2014, 09:08 PM	#4
jailhousebob Senior Member Join Date: May 2010 Posts: 143	Re: '40 merc pinion question I've done several sets,always 6 spline,and it works out great.Plus the orig ford/merc gears are superior the the aftermarket stuff . My guy gets $150.00 to spline the pinion stub .Bob

09-12-2014, 11:12 PM	#5
supereal Senior Member Join Date: Jul 2014 Location: Iowa Posts: 1,634	Re: '40 merc pinion question When we adapt an early driveshaft to a later pinion, we use an adapter. We cut the shaft in our long bed lathe, then turn the adapter to a slip fit. The whole assembly is chucked in the lathe, then welded. Cutting splines is a very complicated and expensive job, so using the adapter makes less cost, and a quick turnaround.

09-13-2014, 01:19 AM	#6
GEOFFNZ Senior Member Join Date: Jun 2010 Location: Oxford New Zealand Posts: 177	Re: '40 merc pinion question Sponsored Links (Register now to hide all advertisements) We have a 39 Mercury3.54 gearset running in 36 housing.The pinion was cut off with a short shaft and splined to 6 splines.Works very well.Cheers.

09-13-2014, 12:17 PM	#7
Fred A Senior Member Join Date: May 2010 Location: Encino California, near Burbank Posts: 935	Re: '40 merc pinion question Hard to imagine that machine work and other handling expenses could be a better idea than buying aftermarket gears. Declaring that the original gears could be superior seems like a shoot from the hip opinion, difficult to prove. 3.54 gears are no longer a premium item. Many guys are finding that 3.27s make great road gears where other gearing and torque producing issues are addressed. I does however sound like a great boast to make over the bench. Good Luck: Fred A

09-13-2014, 04:20 PM	#8
Cecil/WV Senior Member Join Date: May 2010 Location: Gerrardstown, WV Posts: 2,266	Re: '40 merc pinion question I have a Merc rear that is surplus.