Pick & pull rear ends

[Mrturner1]

So I'm knee deep into my engine build and the tranny is getting some love in the near future too. My rear end is stock, and does awesome show stopping 1 tire burnouts. My question is, how do I determine exactly what rear end I currently have AND, is there a rear end I could search for at pick & pull that has a posi and something like 3.42's or 3.73's? My truck is a half ton long bed, if that matters. I'm only limited by my lack of torch or welding capabilities, other than that I'm getting pretty handy with the wrenches.

Also, I'm doing this to avoid taking my truck to a shop and spending 1500 bucks on a posi and ring and pinion. If a swap is really hard or requires welding I can have my rear end rebuilt, just thought to check for easy swaps first

[87Skier]

I've never found a good way of determining whether or not a certain rear end has a locker/posi/lsd without looking at it. You can try looking at the spid, or the RPO codes in the glovebox, but it would be silly to buy one without opening it up first. Sometimes you can tell by lifting the rear off the ground, but that usually relies on having the vehicle in park, which you probably won't have in a junkyard.

I will say that you definitely need to measure your axle width. I know that the 1988-1998 trucks had wider axles since they used a different backspacing on the wheels.

You can determine axle ratio a few different ways. You can rotate the wheels once and count the number of revolutions the driveshaft makes, or open it up and count the teeth.

[NC_John]

Save your money and do a proper rebuild/upgrade on yours. How do you know what you find in the junkyard, sorry- auto "recycler" won't already be shot?

[Mrturner1]

Originally Posted by NC_John

Save your money and do a proper rebuild/upgrade on yours. How do you know what you find in the junkyard, sorry- auto "recycler" won't already be shot?

I hadn't really thought of that. I guess they'd sell it to you even if it was bad or worn.

[hugger6933]

Make sure the truck/car you pull parts from has WRECK damage. they don't get wrecked sitting in a shop waiting to get fixed. 99 times out of a 100 the people are driving down the road happy with their vehicle and aren't thinking of trading it in or getting rid of it before the accident.I've have been building wrecks since 1987 and only have had very few drive train problem from a vehicle that was wrecked. Now repo's and things like that are a different story I walk wide around them I did buy a good bit of watered stuff but only used the sheet metal. i have had great luck with parts being good to very good from the wrecks I buy. just make sure it is wrecked some and not a repo or something like that where you don't know it could have a bad motor trans and rear end. Jim

[stsalvage]

My one ? is you have ladder bar's or leaf springs if you have leaf spring you have a good choice of rear ends out there.

I know from 1964-70 used the same rear end cus they are all 6 lug one difference you you have ladder bars or leaf springs.that on outer housing now the rears will be different.But you find one with a auto th350 and 400 its pretty close to the 3.77 or 3.55.

Any thing new after 1998 and up had really bad casting on there Gears and bearings seen a ton of 1999--2009 Chevy rear shear teeth or crack spider gears Some tell me its the oil additive they used and the weight there where using

[trkfrk]

Here is a really good write-up that one of our members took the time to do.

http://67-72chevytrucks.com/vboard/s...d.php?t=509262

i just ordered new gears and posi off eBay and plan on using the write-up. Good luck.

[truckster]

I have the Auburn posi in my Z28. It works OK, but does have its own quirks and it's not rebuildable.

For a truck I'd look at a lunchbox locker.

[MARKDTN]

Originally Posted by hugger6933

Make sure the truck/car you pull parts from has WRECK damage. they don't get wrecked sitting in a shop waiting to get fixed. 99 times out of a 100 the people are driving down the road happy with their vehicle and aren't thinking of trading it in or getting rid of it before the accident.I've have been building wrecks since 1987 and only have had very few drive train problem from a vehicle that was wrecked. Now repo's and things like that are a different story I walk wide around them I did buy a good bit of watered stuff but only used the sheet metal. i have had great luck with parts being good to very good from the wrecks I buy. just make sure it is wrecked some and not a repo or something like that where you don't know it could have a bad motor trans and rear end. Jim

I will second that. A guy told me the worse it was wrecked, the better it was running when it was wrecked. That has been great advice. The other thing he told me was not to be afraid of burnt engines. Nobody likes them, but the heat wont hurt the long block (at least iron blocks and heads) and you can usually get them for less than a comparable one.

Before that good advice, I bought a nice looking engine from an '87 Olds Ciera, nice clean car. Put it in and it threw a rod on startup. Back to the yard for another. This one out of a rolled car. It ran like a champ until I sold it. Another time bought a Quad-4 from a nice car, oil was full of water-I should have known better on that one. Replacement came from a car nailed hard in the back. Ran like a top.

[87Skier]

x3 on the wreck damage. Anytime i pull parts I always think to myself, why would a vehicle with no body damage be here?

That ring, pinion, posi setup is cheap. I was looking a few weeks ago for a TrueTrac setup and that alone was $475 then you needed gears, and an installation kit.

[Mrturner1]

I was also thinking this would be a good opportunity to switch to a 5 lug. Truck will have disk brakes someday too

[NC_John]

Originally Posted by 87Skier

x3 on the wreck damage. Anytime i pull parts I always think to myself, why would a vehicle with no body damage be here?

That ring, pinion, posi setup is cheap. I was looking a few weeks ago for a TrueTrac setup and that alone was $475 then you needed gears, and an installation kit.

I got one of these kits from Ron's on fleabay.

http://m.ebay.com/itm/1965-1981-CHEVY-12-BOLT-TRUCK-3-42-EXCEL-RING-AND-PINION-EATON-POSI-GEAR-PACKAGE-/271116102328?nav=SEARCH

It is a really nice kit. I had a gm mechanic buddy come over and help me install it.
Posted via Mobile Device