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| | | | Joined: Nov 2010 Posts: 114 'Bolter | | 'Bolter Joined: Nov 2010 Posts: 114 | I am in the process of swapping the diff in my 42 3/4 ton (BL). I have a 55 1/2 ton 3:90 diff & carrier that I want to put into my OE axle. I'm running the OE Muncie 4 speed with granny gear. I've bought 3:38 R&P to use in the 3:90 diff but have been unable to find a good source for new spiders and cross shaft for the GM 55T diff.
If anyone can point me towards a source for good quality spiders, I'd sure appreciate the help.
Tom
Little Egg Harbor, NJ
1942 Chevy (BL)
Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | When you say "new" do you mean new or are good used OK?
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | What are you doing about the two different wheel bolt patterns?
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Nov 2010 Posts: 114 'Bolter | | 'Bolter Joined: Nov 2010 Posts: 114 | Dave:
Thanks for your reply. I spoke with Patrick Dykes in AZ yesterday. He recommended Bob Adlers Antique Auto Parts in NY. Called them today and they have a good used set at $105. I'm sending them a check today.
Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | Good deal!
Ed, 1941-42 3/4 tons used 6 lug wheels. Basically a 1/2 ton with heaver springs.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Tom, "them" - you most likely spoke with "him". He is THE expert. | | | | | Joined: Nov 2010 Posts: 114 'Bolter | | 'Bolter Joined: Nov 2010 Posts: 114 | I am rebuilding a GM 55T diff & carrier only, which will bolt into my OE 42 3/4 ton axle housing (has the same bolt pattern on the pumpkin). As both have 17 spline axle shafts, there will be no issues with the wheel bolt patterns. The only issue I'm aware of is the rear driveshaft will need to be lengthened about 7/8 inch, and the rear universal halves will also need to be matched.
This swap has already been completed by several guys, and I'm told it works very well. Of course..., ya never know till ya try it on your truck but, I don't expect any serious problems.
Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | You should not have any problems with that swap.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Nov 2010 Posts: 114 'Bolter | | 'Bolter Joined: Nov 2010 Posts: 114 | Tim:
I asked if it was Bob Adler on the phone and the guy on the other end said no. He also did not give me his name.
Hence the use of "them".
Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt
| | | | | Joined: Nov 2010 Posts: 114 'Bolter | | 'Bolter Joined: Nov 2010 Posts: 114 | Dave:
Thanks.
As I am running 29.4 inch overall tire diameters, I expect the truck to drive as designed. The mod should just give me a bit better gas mileage, while taking some revs off the 1962 Chevy 235.
I have considered swapping the OE Muncie 4-speed for a Saginaw 3 speed I have on the shelf. I just thought I'd try the R&P change before I got into any trans issues. Being in south Jersey it's pretty darned flat here. Based on this, I'm not too concerned about the use of the low gear ratios in the Muncie with the 3:38 R&P
Ghost Rider
Little Egg Harbor, NJ
1942 Chevy 3/4 ton pickup, 1962 235, Offy intake, Fenton headers, Dual Carter YFs, 1984 T5
1956 Chevy 3100 Apache, 67 350SBC, Saginaw 4 speed, 69 12 bolt
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I see you have a 190SL. I have been keeping a 1961 190Db on the road for about 30 years for one of my customers. Don't tell anyone I work on anything but Chevrolet's though. 
See the USA in your vintage Chevrolet! My Blog | | |
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