Rear end swap question.

[Money_pit]

I've stumbled across a 6 lug 69 c10 rear axle with a 3:73 and a locker. I have a 71 c10 that's a 5 lug 3:08 open rear axle. Will my axles shafts fit the 69 axle? Or would I have to get different rims or adapters?
Thanks in advance. Having that 3:73 and being able to light both rear tires up instead of the wimpy one wheel peel would be great

[Overdriven]

The 70 1/2 and earlier width is 62-3/8" from wheel mount to wheel mount.
The 70 1/2 and later (up to about 78 or so) width is 63-3/4" from wheel mount to wheel mount.

So that's a no go on swapping the axles. If it was me I'd avoid spacers and unless you want to change the backspace or something I wouldn't get new wheels either. You don't want the front to be 5 lug and the rear be 6 lug, then you'd definitely need 2 spare tires. The easiest option is getting new narrow axles in 5 lug for the 1969 rear and swapping them in. New axles wouldn't be that much more $ than good adapter/spacers. It's either that or swap the gears and carrier between housings.

[leftybass209]

Yeah, axle swapping is a no-go. However, since it probably already needs (or could benefit from bearings) you could always have the axles drilled for 5 lug.

[Money_pit]

Thanks for the quick response everyone. I am liking the idea of having the 6 lug shafts drilled for the 5x5 I'm thinking that's the direction I'm heading. Thanks again.

[truckster]

The 3.73 ratio is a good one. One word of caution - you mention it has a locker. Is it a true locker, or is it a Gov-lock? If it's a true locker, go ahead and light the tires all you want. However, if it's a Gov-lock it's eventually going to grenade on you, and the more you light them up the quicker it's going to happen.

[RodnRudy]

Don't forget that when you have the axles redrilled you also have to have the center register hub turned down to fit the five lug brake drums. Around here, Indy, that's about $250.00 for the machine work. You can find a five lug axle and brake drum kit from the vendors on the forum. Might want to go that route.

[Jrainman]

So tell me why he could not take the 69 3.73 gear and carrier and put it in the 71 housing using the 71 5 lug axles are they not both 30 spline axles .

[LongBox]

Or, as another approach, why not change the front hubs to 6 lug?

[Tquillen]

I have wrestled with the same dilemma on my '69, which was originally 6 lug drums. My two issues were the narrow rear track width (a 235/75/15 actually rubs the inner fenders!) and the lack of a factory offering for a six lug disc brake rotor. There are aftermarket rotors available, but one thing I am trying to maintain throughout my modifications is to use off the shelf parts wherever possible, especially on wear items like rotors. My solution involved purchasing an '87 rear end assembly, which is the 8.5" ten bolt, and is also wider in width. This particular rear came out of a 4x4, so it has the wider rear drums (one thing I really wanted for my C10). I'm redrilling the axles and turning down the centers myself to the 5x5" pattern, and have bought 2" drop spindles along with 73-87 5x5" front HD rotors. This way, I can buy all the parts at most any parts store, regardless of where I am with the truck.

[Money_pit]

At this point I'm asking myself should I just keep my rear axle and change gears and a locker for my current setup? Or do I just get the six lug shafts drilled for 5x5? And roll with it eventually I'd like to put this truck on bags. I was trying to swap these parts for a fix while I save up some more dough.

[midniteblues]

Originally Posted by Jrainman

So tell me why he could not take the 69 3.73 gear and carrier and put it in the 71 housing using the 71 5 lug axles are they not both 30 spline axles .

He can but it will require pretty much a whole rebuild with a new crush sleeve and shim set up since both axle houseings are not perfectly machined with identical bearing saddles.and both gears set require differnt shim stacks since they are not the same series carrier.

Setting up used gears is way harder than new gears.

Youll have too weld up some intersecting stud holes When drilling for the studs. And the stud holes "should" be knurled.

[Overdriven]

Originally Posted by RodnRudy

Don't forget that when you have the axles redrilled you also have to have the center register hub turned down to fit the five lug brake drums. Around here, Indy, that's about $250.00 for the machine work. You can find a five lug axle and brake drum kit from the vendors on the forum. Might want to go that route.

He already has 5 lug drums on the 71 axles, any reason he'd have to replace them besides wear? I mentioned getting 5 lug axles for the 69 rear in my first post in this thread as it seems like the most simple option, just trying to make sure there aren't any compatibility issues besides possible tire clearance issues.

[Money_pit]

Should I really be concerned with tire rub? Thought there was only a little over an inch difference in the width. Almost seems as though it's about the same cost just to rear gear my lug axle and be done. Sounds like I've got some decisions. Thanks guys

[Overdriven]

Originally Posted by Money_pit

Should I really be concerned with tire rub? Thought there was only a little over an inch difference in the width.

It depends. If you have wide aftermarket wheels and tires with very little clearance to the inner fender now, going to a narrower housing will put the tires even closer and possibly rub. I don't know exactly what you have but mention this variable so you can rule it out before swapping.

[seafoam68]

I believe I would sell the six lug rear end and just replace the carrier and gear in the five lug with it in the truck. The money spent to convert the six lug would probably be about the same to do this. Plus you wouldn't have to deal with pulling rear end out of truck. Those u bolts can be a pita sometimes.

[midniteblues]

Originally Posted by Overdriven

He already has 5 lug drums on the 71 axles, any reason he'd have to replace them besides wear? I mentioned getting 5 lug axles for the 69 rear in my first post in this thread as it seems like the most simple option, just trying to make sure there aren't any compatibility issues besides possible tire clearance issues.

Jfyi 5 lug and 6 lug drum brakes are not the same. There is a width and diameter differance between the two.

[Money_pit]

Thanks for all the advice. I'm leaning towards just having my current axle re geared and saving the six lug for the next build.was hoping it would have been a simple fix should have known better.

[randy500]

Measure the width backing plate to backing plate to find if the axles will fit. My experience which is a lot is that 1969 housing width is the same as 71-2. I did it once on a leaf spring rear end.

[Money_pit]

I will definetly check first. I'll post my findings won't be till the weekend