The Ford Barn

phil pavicich · 04-02-2017, 12:44 AM

Im about to fit a 40 banjo with stock straight spring into a 34 chassis , with stock curved crossmember , is it ok to slightly grind spring pack to fit . i saw photos on here some where but cant find them .thanks in advance

Mart · 04-02-2017, 03:06 AM

I've never done it, either, but have also read the write-ups of it being done. I will add, though that most of the instances I have seen have been roadsters, it might not be a great idea on a heavier car like a 4 door sedan or pickup. Again, no personal experience, just a gut feeling.

I believe people have used a front spring from a 42-48, which will work, but I don't know the details of which shackles will fit, or how heavy the cars were.

Mart.

rich b · 04-02-2017, 04:12 AM

http://www.fordbarn.com/forum/showth...ghlight=spring

http://www.fordbarn.com/forum/showth...ghlight=spring

Worked on a few '32's with a straight spring ground this way.

Have also heard that it doesn't work on '33-'34 due to differences in the cross-member shape.

hotrodA · 04-02-2017, 10:15 AM

Just did it with a 37 rearend and spring, but the 34 crossmember is in my 32. Ground about 1/8" off.

V8COOPMAN · 04-02-2017, 03:41 PM

A STRAIGHT spring is probably going to make your rear end sit too far to the rear, or to the front, or.....who knows? That would effect your torque tube and drive shaft lengths, as well as the car looking "funny" if it has rear fenders. DD

Andy · 04-02-2017, 04:01 PM

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I cut the 40 hangers off and moved them to the 32 positions for my 32 change over. I made a weld fixture to fit the 32 rear end hangers to get the 40 hangers in the right position. This retains the axle position and ride heigth. It also retains the ride.
It also allowed be to rotate the bells 180* to get better stub axle bearing surfaces.

Flatout · 04-02-2017, 08:36 PM

A small amount of grinding on the rear of the straight spring will allow it to slip right into the crossmember. Even less is needed to fit into a 32 crossmember.
I've done this several times over the years.

deuce_roadster · 04-02-2017, 08:51 PM

As stated above, you don't have to grind too much off a 40 spring. That is what is in my avatar roadster, a 40 rear end with a shortened TT and driveline.

phil pavicich · 04-03-2017, 06:14 PM

thankyou for your replys

04-02-2017, 12:44 AM	#1
phil pavicich Member Join Date: Aug 2010 Location: australia Posts: 58	Fitting A 40 diff into a 34 chassis Im about to fit a 40 banjo with stock straight spring into a 34 chassis , with stock curved crossmember , is it ok to slightly grind spring pack to fit . i saw photos on here some where but cant find them .thanks in advance

04-02-2017, 03:06 AM	#2
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,756	Re: Fitting A 40 diff into a 34 chassis I've never done it, either, but have also read the write-ups of it being done. I will add, though that most of the instances I have seen have been roadsters, it might not be a great idea on a heavier car like a 4 door sedan or pickup. Again, no personal experience, just a gut feeling. I believe people have used a front spring from a 42-48, which will work, but I don't know the details of which shackles will fit, or how heavy the cars were. Mart.

04-02-2017, 04:12 AM	#3
rich b Senior Member Join Date: May 2010 Location: Minnesota Posts: 1,827	Re: Fitting A 40 diff into a 34 chassis http://www.fordbarn.com/forum/showth...ghlight=spring http://www.fordbarn.com/forum/showth...ghlight=spring Worked on a few '32's with a straight spring ground this way. Have also heard that it doesn't work on '33-'34 due to differences in the cross-member shape. Last edited by rich b; 04-02-2017 at 04:22 AM.

04-02-2017, 10:15 AM	#4
hotrodA Senior Member Join Date: May 2010 Location: Rogersville, TN Posts: 797	Re: Fitting A 40 diff into a 34 chassis Just did it with a 37 rearend and spring, but the 34 crossmember is in my 32. Ground about 1/8" off. Last edited by hotrodA; 04-02-2017 at 05:21 PM.

04-02-2017, 03:41 PM	#5
V8COOPMAN Senior Member Join Date: May 2010 Location: East Shore of LAKE HOUSTON Posts: 11,115	Re: Fitting A 40 diff into a 34 chassis A STRAIGHT spring is probably going to make your rear end sit too far to the rear, or to the front, or.....who knows? That would effect your torque tube and drive shaft lengths, as well as the car looking "funny" if it has rear fenders. DD __________________ *Click Links Below* __ ▼ *'35-'36 W/8BA & MECHANICAL FAN* *T5 W/TORQUE TUBE* Last edited by V8COOPMAN; 04-02-2017 at 03:52 PM.

04-02-2017, 04:01 PM	#6
Andy Senior Member Join Date: May 2010 Location: Kerrville, Tx Posts: 2,771	Re: Fitting A 40 diff into a 34 chassis Sponsored Links (Register now to hide all advertisements) I cut the 40 hangers off and moved them to the 32 positions for my 32 change over. I made a weld fixture to fit the 32 rear end hangers to get the 40 hangers in the right position. This retains the axle position and ride heigth. It also retains the ride. It also allowed be to rotate the bells 180* to get better stub axle bearing surfaces.

04-02-2017, 08:36 PM	#7
Flatout Senior Member Join Date: May 2010 Location: Damascus Oregon Posts: 160	Re: Fitting A 40 diff into a 34 chassis A small amount of grinding on the rear of the straight spring will allow it to slip right into the crossmember. Even less is needed to fit into a 32 crossmember. I've done this several times over the years.

04-02-2017, 08:51 PM	#8
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,800	Re: Fitting A 40 diff into a 34 chassis As stated above, you don't have to grind too much off a 40 spring. That is what is in my avatar roadster, a 40 rear end with a shortened TT and driveline.

04-03-2017, 06:14 PM	#9
phil pavicich Member Join Date: Aug 2010 Location: australia Posts: 58	Re: Fitting A 40 diff into a 34 chassis thankyou for your replys