What year Rear end ??

[Chvy2NV]

My truck is a 67 SWB. I'm looking at changing out my 6 lug for a 5 lug. Is it better to just buy a 71-72 rear end with 5 lug or should i convert my original one. I read somewhere that some specific years have wider rear ends so that makes me concerned with wheel size figment. What are the better rear ends 67-70 or 71-72??
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[SS Tim]

When the factory went to disc brakes (71-72) the wheel track increased a little. To match it the factory increased the rear axle width. It is not a matter of better, just different. If you are converting to five lugs just for disc brakes then swap the rear. If you need to keep a narrow track to match up to say narrowed front a-arms then use conversion axles.

[Chvy2NV]

Thanks for clearing alot of that up Tim, I apologize for the noob questions but wheel spacing and that kinda stuff has never been my strongest point..

I plan on eventually upgrading the front end with PB front crossmember and tubular a-arms.. Im not sure if these are narrower than the OE 67 ones im currently running.
When I say"better" i guess i meant preferred as far as for wheel options and getting a more aggressive wheel lip/width.

I have access to a SWB (71-72) 12 bolt main which measures 56 1/2" from backing plate to backing plate.

Does that sound right ??

Originally Posted by SS Tim

When the factory went to disc brakes (71-72) the wheel track increased a little. To match it the factory increased the rear axle width. It is not a matter of better, just different. If you are converting to five lugs just for disc brakes then swap the rear. If you need to keep a narrow track to match up to say narrowed front a-arms then use conversion axles.

[cleanfreak]

Why would you want to change? the wheel / tire combo works on your truck - it looks right. I've messed with this same question on my 68 , it only has 8" rears , re-drilled axles , disk brakes on front with 7's. Had to put on 1 1/4 spacers on the rear to look "right". I have pictures to show the difference if you are interested.

[weaintscared]

I bought one from a 72 to go in my 69

My build http://67-72chevytrucks.com/vboard/s...ar#post4724684
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[CC69Rat]

Heres the actual lengths, and why Im thinking the rear end housing swap is not the way you want to go.

67-really early 70 model trucks have a narrower rear end housing. If you measure from the inside of one backing plate to the other, the early ones are 55.5" and the late ones are 57"

The 56.5" measurement tells me its likely the later rear end housing youd be swapping in. Sounds right for the 70-72 model years. 1970 model trucks can have either. I have a 70 gmc with the late housing in it. For the most part in early 70 they just used what they had at that time.

If you have an early housing now and want to change to 5 lug, finding original gm axles is going to be near impossible. In fact I dont recall ever seeing them. Most early axles were 6 lug.

If you find the axles available, measure from the mounting surface of the axle to the end of the splines. The early ones are 30.5" long. Late ones are 31 5/16.

Now, consider your wheels.. say you have the early rear end housing now and you change to the late housing.. you will be adding. 75" in width on either side. Your wheels and tires will stick out. 75" more on either side. If its the truck in your avatar now were talking about it looks pretty stuffed now. Do you have. 75" clearance on the fenders/ bed sides?

Personally Id get a set of early 5 lug axles from Moser, new bearlings and seals and get it wrapped up like that. The narrower housings are more desirable for lowered ride heights. You can just fit more tire under the truck if you like the'tucked' look. Hope this helps.
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[sighlurr]

Does anyone have a picture of one rearend vs the later in the same truck with same tire/ wheel/ offset, etc? I'm having a hard time picturing what .75" per side really would look like...

[Robznob11]

you can get aftermarket axles from moser, strange and other places that will fit right into your housing and then you change drums. the axles are 300 bucks and a lot stronger than oem's my self I like a little more tire in the back and would not want to give up that 1.5" id make it up in wheels and tire first. I called moser and got mine they had the specs and I told them to use a car bolt pattern and turn the center hub down. then I used car drums and whalla I can get rims of any size and width cheep!

[tmc1986]

TBONE1964 posted this on another thread. http://www.brotherstrucks.com/prodin...number=RAC6569 hope it helps

[CC69Rat]

If you're sure its a narrow housing, Just me.. Id stick with that one. It may cost you a few more dollars at first but. 75" tire clearance is huge when you have a 5-6" drop.

Ex: most of the guys running 20s will do a 20x10 with 5" bs on a narrow housing. BUT you need 5.5" for the wide housing (still. 25 wider but its tough to find 5.75" bs unless you do the high end wheels)

My point is the same width wheel will have more of the'lip' look with the narrow housing. Were talking about an inch max here but the lower you go the more precious this space becomes.

Id do Mosers. Just measure your housing to be sure its 55.5" from inner backing plate to backing plate. 63-70 axles on the Moser site, 30.5" long.

Have you swapped axles before? Its not terribly difficult to do.
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