I'm currently working on a mid 80's Dodge full size truck. It is a 2 wheel drive with the stock 318 engine, 727 and the 8 1/4 rear axle in it. Unfortunately, the truck does NOT have a sure grip. It really needs a sure grip!!

Were the auburn style sure grips used in all the 8 1/4 and 9 1/4 axles?

Switching to a 9 1/4 axle is an option. Is there any reason to swap in the larger axle?

No reason to get a 9-1/4 for a stock 318. Unless you get a good deal on a 9-1/4 with a sure-grip already in it. You can get a Mopar performance part number P4529273 sure grip carrier at Summit for around $375, unless I just bought the last one. You could possibly find one in a 1995 or older dakota in a salvage yard for cheap, but it could be worn out. Difference is 96 and newer uses 29 spline axles and 95 and older has 27 splines.

Not sure where your located

https://sheboygan.craigslist.org/pts/d/mopar-dodge-plymouth-chrysler/6459175240.html

new trak loc unit will run $500 ish

Plus installation?

I went with the lock-right locker that replaces the spider gears in the carrier on my 9 1/4, installs with hand tools and is one tuff piece for the price 300-400$ have them for 8 1/4 also.

another upgrade is to replace the crush sleeve to solid spacer on the 8 1/4 and 9 1/4

the c-clip axles/spider gears are the weak spot with wieght/high traction/slicks for either 10 bolt or 12 bolt SB & BB combos.

I would use clutch pack type sg over a cone sg or locker.

my 88 440 truck runs A-body 8 4/3 tucking 12" rims 29x15x15 M/Ts

and the 85-318 stepside has the 67 C-body 8 3/4 tucking 10" rims 30x9.50 tires.

I removed the 3.55 9 1/4 last week for the 8 3/4 fast gear change

it now waits for something to go back in.

depending on what you want to do with the truck depends on $ and what rear axles works best.

I like the 8 3/4 in my trucks for fast gear changes and having several to choose from under the bench helps go from work truck to drag truck with hand tools.

www.doctordiff.com has your answers and parts. Trac-lok for 8.25 is $365, for 9.25 is $300.

The Lock-rite and others that drop into stock open differentials are lockers, not limited slips. The axles are either locked to each other or one unlocks and is freewheeling.

PowerTrax is now selling limited slips, and Yukon has a decent looking 9.25" limited slip. There are others, too, I'm sure. It's interesting that prices have diverged with some going lower and some markedly higher than they used to be.

R.