Re: Source for 83/4 Sure Grip Gears

Bill,

I just sent another explanation. The difference is only with tapered axle units and their thrust blocks. Has nothing to do with the rear end, it's the axle lengths. This Group is for 62-65 owners and only messes up 62-63 units. Your 65 is the better unit.

Nick T.

From: "Bill M" <y1topbanana73@xxxxxxxxx>
Subject: Re: Source for 83/4 Sure Grip Gears

Nick,

So what exactly is different between the 741 & 742 setups? It was always my understanding that 8.75 rear chucks were completely interchangeable...regardless of year. Or is this a tapered axle issue only (which I've never had)?

Thanks

Bill M
65 Coronet 500 'vert http://goo.gl/6xUS1
73 Dart Sport, 05 Ram 2500 CTD, 4WD, QC, LB, Laramie
12 Journey R/T, 14 Avenger R/T, 21 Model T Depot Hack

On Fri, Oct 14, 2016 at 11:17 AM, <furyus63@xxxxxxxxxxx> wrote:

I purchased my 742 3.55 SG unit from Randy's, when I could not reinstall my axles their tech support could not help. I wrote a tech article years ago to the 62-65 site with this info. I do not believe any of the rear gear outlets have ready made 741 units any longer, mostly 742 or 489. I have never found documentation on the axle length for a 741 SG unit.

Nick T.

From: "hmsevans via The 1962 to 1965 Mopar Mail List Clubhouse" <1962to1965mopars@xxxxxxxxxxxxxxxx>
To: "1962to1965mopars" <1962to1965mopars@xxxxxxxxxxxxxxxx>
Sent: Friday, October 14, 2016 10:58:03 AM

Subject: Re: Source for 83/4 Sure Grip Gears

Nick

What about buying a new 741 New unit from Dr Diff or Randy's Ring and Pinion ,Will they work in the stock unit if I shorten the axles ?

-----Original Message-----
From: furyus63 <furyus63@xxxxxxxxxxx>
To: 1962to1965mopars <1962to1965mopars@xxxxxxxxxxxxxxxx>
Sent: Fri, Oct 14, 2016 10:42 am
Subject: Re: Source for 83/4 Sure Grip Gears

A 741 carrier with 3.55 Sure Grip is difficult to find now a days, but there are some out there. The most common upgrade I know of is to replace the 741 non-Sure Grip with a 742 Sure Grip unit which is more than for your street use only.

The problem is axle length with your '62 tapered axle 8 3/4 unit. Both axles must be shortened 1/16" to be able to obtain the .013 to .023 inch axle shaft end play which is required.

Axle length 2070573 741 case w/o SG 30 1/2"
Axle length 2404050 742 case w/SG 30 7/16"

The axle for a SG unit is 1/16" shorter than the non-SG unit. It took about 45 minutes each to grind down and dress the axle end.

Nick T.

From: "hmsevans via The 1962 to 1965 Mopar Mail List Clubhouse" <1962to1965mopars@xxxxxxxxxxxxxxxx>
To: "1962to1965mopars" <1962to1965mopars@xxxxxxxxxxxxxxxx>
Sent: Friday, October 14, 2016 10:17:15 AM
Subject: Re: Source for 83/4 Sure Grip Gears

Nick
That is exactly want I want to do, Its a 741
Thanks

-----Original Message-----
From: furyus63 <furyus63@xxxxxxxxxxx>
To: 1962to1965mopars <1962to1965mopars@xxxxxxxxxxxxxxxx>
Sent: Fri, Oct 14, 2016 10:03 am
Subject: Re: Source for 83/4 Sure Grip Gears

Mark,

I've done this conversion before. Most likely the gear in the carrier is a 8 3/4 2.76 non-Sure Grip and you're wanting to replace it with a 8 3/4 3.55 Sure Grip. The important question is what carrier do you have, a 741 or 742. There may be a slight modification for you to make which I can explain later.

Nick Tiberio
FuryUs63

From: "hmsevans via The 1962 to 1965 Mopar Mail List Clubhouse" <1962to1965mopars@xxxxxxxxxxxxxxxx>

Subject: Source for 83/4 Sure Grip Gears

Starting to rebuild the components for my 62 Plymouth,413,auto
I have the rear end disassembled and cleaned.I have 2.73 std gears .I want to replace with a 3.54 sure grip for the street use only.
I plan to use the stock axles and 14" drums brakes on the rear, but use the drum conversion kit.
What is the most reliable New Gear sure grip set package that I use?
Mark