Rear Posi (is it worth the money)

[weasel29gm]

If you build a truck or car and do old school or modern with motors or tranny's built.And don't go with posi or limited slip whatever you call it your spinning your wheels 😅 no pun intended lol!!! 3.73 factory posi in mine never a problem wet or dry. I don't need a owners manual to tell how to drive wet or dry. Common sense prevails!!! I've read a lot of posts here in 20 plus yrs and running cruise wet conditions maybe one of best ones so far, as a old quote says " Some people raise the dummies kids"...... Dang a little of Grumpy out of me 😆

[MikeB]

Originally Posted by truckster

I put in a 1981 Buick Estate Wagon that had previously been home to an Olds diesel. Just for fun I left the diesel badges on it. It's one of the ones I kind of wish I still had.

In the early 1980s I special ordered an Olds Cutlass wagon with the diesel engine. When it arrived on the lot several weeks later, I jumped in and fired it up. After 20 seconds, my wife and I looked at each other and said almost in unison: "I don't want this noisy thing!" The salesman told us it was no big deal, because diesels were starting to sell for list price!

Always wished I would have ordered a gasoline engine, because it was a very nice car. Light yellow with the tan vinyl interior that I've always loved in GM cars. It also had an excellent instrument panel with a the gauge package.

Seems to me it had bucket seats. Could that have been correct? Am I off on a tangent here, or what?

Super cool instrument cluster, IMO.

[truckster]

The Cutlass probably had buckets. The Estate Wagon was bigger (Delta 88 size) and hand the plush red velour interior. It was like driving your living room sofa, but with incredible amounts of torque.

[LT7A]

Originally Posted by 3drburb

I guess I will agree to disagree with all that, as I drive in the same weather with no Posi without spinning from stop to start and I live on one of the biggest hills in Kent driving a Chevy Express about 5 days a week for work.

Thanks for the education.

Wow! All the trucks and cars that made it building the world and farming and daily use along with being enjoyed with the non Posi all these decades while spinning tires not being able to move when it's not sunny and they are still building millions of them, Even the OP truck made it this long without.

Btw, I also have classic cars with a Posi.

Driving an Express Van versus driving an empty pickup is not a valid comparison. Although, if I had the chance, I would order posi in a van as well.

I hope you got what you wanted out of your mockery comments. Prior to that, we were having a pretty reasonable discussion. But you have made me think about it. I will probably stop getting posi on trucks that others drive - it could be detrimental it they're not comfortable with it.

In service of the original question: Limited slip differentials are simply a traction aid. If used correctly they operate as designed and help in power vs limited traction conditions. For me it's simply a case of what the best tool for the job is. I'm comfortable driving with a posi and I know how it works and how it can work against me and prefer to have the traction advantage, work or hobby. But especially on my hobby rig. Do I need a hobby truck? No. Does what I have need more power? No. Do I need positraction? No. Do I want a hobby truck with more power and the best chance to use it? Sure thing.

[3drburb]

You were making fun of all the trucks without a Posi, so I stated my facts.
I like to read your post so and wasn't trying to offend you in any way.
As for empty pickup, I may not post every vehicle I own on here.
I have owned and driven a 1989 1500 2wd non posi off and on for 20 years, as I own a business and only use my van for that business, nothing else.

Apologies to all reading this including you if it went in the
wrong direction.

[MikeB]

Originally Posted by 3drburb

Wow! All the trucks and cars that made it building the world and farming and daily use along with being enjoyed with the non Posi all these decades while spinning tires not being able to move when it's not sunny...

But they sometimes got stuck in mud at job sites, or even on the farm.

No one here ever said you couldn't go down the road w/o posi, only that it helps in some situations.

Cheers!

[3drburb]

Originally Posted by MikeB

But they sometimes got stuck in mud at job sites, or even on the farm.

No one here ever said you couldn't go down the road w/o posi, only that it helps in some situations.

Cheers!

That cut and paste quote was the reply to #30 post, implying that a non posi was useless in the rain or on wet roads or going up hills. The PNW is wet most of the times with a lot of hills.

Now I will go back to reading as usual and enjoying useful information.

[Accelo]

How about the Gov Lock?
Only locks up below about 30mph.

https://youtu.be/D9Eq8aPt8ps
I have one in my 2000 Silverado. 170K without issues.

[chevmn]

I recall the first vehicle with G80 rear axle I had. I purchased it, and really never knew the difference or that it had a posi rear. I purchased it for multiple reasons, but mostly because it was a 4x4. In 1979, they were just becoming popular, and at least in my area, were the exception not the norm like today. Being 19 at the time, I looked for reasons to use 4x4, and it did not disappoint, and I soon found I could go places most could not, and later found out that the posi added one extra wheel with traction (3 as front axle was not posi). I owned the truck 14 years, and was only stuck one time, going places few could, and after i got out of the truck, I knew why. It was buried. The front hubs were below ground, and I did not have to step down to get out of the cab. I traded for a 92 K1500 non-posi 4x4, and wow what a difference, the 92 was a good truck, but on a grade you had to engage 4 wheel drive to move in wet grass. I now have a 2011 with G80 and 4x4, but not a big fan of the newer lockers. My 72 has a dana powerloc, and seems pretty impressive, but it will not likely ever travel a snow covered road, but leaves a nice "carbon footprint" when opening up the big block :=}

[LS short box]

Just to add some video search google and My Cousin Vinny. Fast forward to when they are stuck in the mud with no posi in the caddy. LOL.

[1969stepside]

mt truck has a 327 bored 40 over with a set of dart iron eagle heads with 202 160 valves on 64cc chamber heads with a eblebrock air gap inake fed by a qjet. cam (Int/Exh): 262/268; Duration @ .050 (Int/Exh): 219/227; Gross Valve Lift (Int/Exh): .468/.489; power stearing and brakes and ac

[LT7A]

Hey, 1969, after all that discussion, I saw that no one commented after you posted the specifics and modifications to your engine. My input is that yes, you have invested in making power in a fairly serious manner. I'd love to be able to have a set of Dart heads myself. I think that posi is a logical next step when you put that much money into an engine. You're going to be making some decent power and torque, and generally speaking, posi is what is what can help you use that power. Obviously tires are important, and other suspension components, but if had made those engine modifications, posi would probably be the next thing on my list. I think you'll also need some lower gearing to take advantage of those engine modifications. You said it's a fun truck, not a dd. Going to at least 3.42, and probably 3.73 is what is going to take advantage of the modifications you made to the engine. Then posi will help you hook up that power. Obviously you need to consider what the gears will do to highway RPMs if you drive much at highway speeds.

In kind of a summary, I would say that you generally would not need posi with 3.08 gears. But improving a motor to the point of having high performance heads, I would definitely change the gears and install posi.

[novaX522]

Originally Posted by 1969stepside

mt truck has a 327 bored 40 over with a set of dart iron eagle heads with 202 160 valves on 64cc chamber heads with a eblebrock air gap inake fed by a qjet. cam (Int/Exh): 262/268; Duration @ .050 (Int/Exh): 219/227; Gross Valve Lift (Int/Exh): .468/.489; power stearing and brakes and ac

Nice combo! I have a stock 350 Vortec. When it’s ready for a rebuild I’m thinking a cam along those specs. Something to make more power, but still have good vacuum.
Totally agree with LT7A, a truck like that deserves a posi.

[MikeB]

1969Stepside -- Nice 327 build!

Maybe I missed it, but I didn't see which transmission your truck has, or how tall the rear tires are. Those are factors in determining which axle ratio to use for spirited performance. Your 3.08 may work fine if the trans is a TH350 with a slightly higher stall converter and/or 26-27" tall rear tires. But with 29" tall tires, things may be a bit sluggish, especially with a 327 and a 219/227 cam.

My 69 once had a mild 383 with a 3.08 axle, and a TH350 with Hughes 2000 converter. That thing would smoke the tires in low gear and do a serious chirp on the 1-2 shift. However it probably made at least 50 lb/ft more torque than your 327.

Looks like a good site to calculate and compare tire dimensions.
https://www.calculator.net/tire-size-calculator.html