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| | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | I got my new pumpkin today. The only issue is I don't understand what is stamped on the ring gear.
It ia a 72 3/4 ton center carrier. The guy guaranteed it was a 4:10. I don't understand the numbers on the ring gear it says "GM 10:41"
(then there is a bolt)
"12 (space) 1970"
What gear ratio does this equate to???
Thanks
Rich
| | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | The ratio is 10 teeth to 41 teeth or exactly what you wanted.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Thanks Oldsub,
This was a risk as the junkyard guy I got it from did not seem well versed in these. I checked the code and it was TAJ which is a 4:10 gear 3/4 ton from a 1971.
I can't wait to get it in. I will be away this weekend so it will have to wait.
Rich
| | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | This pumpkin is kind of grimey. There is some grit in the gears. Can I just flush it out with WD40 or do I need to use a different solvent or process to be sure it is thoroughly clean. | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | Congratulations! My 410 pumpkin allows me to drive on the highway and really enjoy my truck. You should try and clean all the grime that you can out of it. I would even suggest an oil change after a few weeks driving with it. | | | | | Joined: Apr 2009 Posts: 431 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 431 | 410 pumpkin allows you to drive on the highway?
what was previously in it? | | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | A 4.57 gear ratio Red, and those were not very highway friendly with a 216 engine. Fred is refering to driving at what is typically called highway speed, i.e., 55 mph. Since you haven't told us anything about yourself It's difficult to tell what your are driving or what your background is. The older three quarter and one ton trucks were geared made for hauling a heavy load with limited horse power so the high way speeds topped out at 40-50 mph.
Denny Graham
Sandwich, IL
Last edited by Denny Graham; 09/03/2009 11:31 AM.
Denny G
Sandwich, IL
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | My truck originally had 5.14 gears in the rear. It now has the 4.10 set and with my 16" LT750 tires, I am turning about 2700 RPM at 60 mph. As Denny says, 50 to 55 is fine for most of my travels. | | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | The guy I got this from said he found 4 of them in his search (they are a nation wide locator)It was not cheap ($385 with shipping) but cheaper and much easier to install than other options.
If anyone is looking for one let me know I will send you their contact info. I looked online for 2 months and was concerned that there were few of these left. These guys found 4. The first had a chipped ring gear and was deemed not salable. They sent me one of the others. I had it within 1 month of first contact.
Great service..very accessableby phone and email.
Rich
| | | | | Joined: Jun 2008 Posts: 47 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2008 Posts: 47 | Check out: www.67-72chevytrucks.comGM 3/4-Ton Eaton HO52/72 rearends with 4.10 gears can be found for sale quite often on this web site. Dan Michalak 1949 Chevy 3600 | | | | | Joined: Dec 2005 Posts: 2,557 'Bolter | | 'Bolter Joined: Dec 2005 Posts: 2,557 | Divide 41 by 10 and you get 4.10 ratio .
1951 3100 Chevrolet1951 Chevrolet Suburban CarryallImage"A house is built with boards and beams. A home is built with love and dreams." "Look deep before you leap !!!" / "Everything is Everything" "If I say a mouse can pull a house, hitch him up"
| | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | Price sounds about right Rich, I paid $250 for mine but I had to drive from Sandwich, IL to Rhinelander, WI., 325 miles and 6hours one way. Needless to say I was very relieved when I pulled the cover off the back and checked out the gears and bearings and found them to be in great shape and no metallic in the oil. When you figure the $150 for gas and a full 12hour day it comes out about the same or a little more than yours.
Check out the bearings and gear lash real good before you install it. If something goes to hell in that rear end you taint gonna find parts to fix it. If you find bearings your gonna pay an arm and a leg for them.
Denny Graham
Sandwich, IL
Denny G
Sandwich, IL
| | | | | Joined: Apr 2009 Posts: 431 Shop Shark | | Shop Shark Joined: Apr 2009 Posts: 431 | right - 'highway speed' of another era. my '60's' cj5 had 5.10s with a saturn od and it was still a screamer at highway speed. i'm not driving it yet, but i have a '50 216 3100, and guessing that it has a 4.10. closed of course. but the 4.10? is coming out, and the open '55 3.90 is going in. i got the '55 and the straight front for $100. the 216 is also coming out and the 235 is going in | | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Dan,
I put a dozen posts on that site and checked daily for a while and never found one there. I think it is all in the timing.
Anyway I have heard of prices on these from $175 to $350. I think I did ok since I just had to wait for it to arrive. It looks in good shape. I cleaned it up tonight and I loosened all the bolts on the existing pumpkin and axles, drained the oil and removed the drive shaft. I hope to install the new one tomorrow and test drive.
RB53 | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | If you end up getting rid of your old one, keep the yoke. You can't buy them anywhere. | | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Truckernix,
I will likely keep the old one for now...just in case. But thanks for the advice. | | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Got the pumpkin in between Friday night and Saturday morning. Took it for a test drive and man am I happy.  Cruise at 55 to 60 on the highway without pushing the engine too hard. I still don't need 1st but 3rd is now a much better gear for cruising around town. My only question is should I have gone with 3:90s  | | |
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