Six Lugs to Five lugs

[JWQ]

New to the Chevy truck stuff. I have a 70 c 10 that we want to lower a little bit and possibly put some power disc brakes on the front. was wondering should I convert to 5 lugs at this time since I would have to order a kit for the front end. Is there any advantages/disadvantages? Asking for more experience opinions. THanks In Advance

[dagnabbitt]

I am planning to do the same and have been having trouble selecting the right kit.

Much more wheel options in five lug, I think that is pretty much the main advantage.

You may already know this but there are two different 1970 rear axles, one is narrower than the other, so you have to measure if choose to do the conversion.

[JWQ]

I did not know that about the axles. Let me know which kit you select ?

[raggedjim]

For the front https://67-72chevytrucks.com/vboard/...d.php?t=444815

You can get 5 lug in the rear a bunch of different ways, the easiest is to find a 71-72 rearend and change it in. I'm assuming you have trailing arms, if you have leaf springs I'm not so sure. You can buy conversion axles also from various places. Or you can use a 73-87 rear axle if you weld on the trailing arm brackets (https://www.rydmanranch.com/product-...rm-axle-mounts). Or, if you are really ambitious, you can have the axles redrilled for 5 lug (probably the hardest way unless you have a machinists friend).

[LS short box]

For the rear axles give Moser a call.

[JWQ]

Thanks for the information, also I saw a Youtube video that said the 73-87 front spindles would bolt into the stock 70 front a frames , does anyone know for sure?

[CC69Rat]

JWQ - welcome to the board.

As previously mentioned, there were two different widths of the rear axle housings in our trucks. The early trucks had a more narrow housing width. Around the mid year production in 1970, GM added 3/4" width to each side to adjust the rear track width. When they started offering disk brakes in 71 the front track width was widened .. the extra width in the rear was necessary to kinda match them up.

So the 63- early 70 trucks will have the narrow axle housing from the factory. If you lay down under the truck and measure from the back of your rear brake backing plate over to the other side in the same place. This width will be 55.5" all narrow housings will be 6 lug.

In the middle of 1970, and the introduction of the wider housing.. they were still 6 lug. But, the plate to plate measurement will be 57"

71-72 trucks would be 5 lug of course.. 57" wide

The 70 trucks could be either. 55.5"or 57" housing. 6 lug. I guess they just used up the inventory of the narrow housings until they were gone. So your truck could be either. If you decide to swap axles this is pretty important to find the correct ones

55.5" early housing will use a 30.5" axle if you measure from the end of the axle splines to the wheel mounting surface of the axle. The late axles are 31 5/16" long.

63-70 conversion axles from Moser are really awesome. I have converted several. It's not terribly difficult.

If your housing is 55.5, you want the 63-70 axles. 57 get the later ones


There are a ton more wheel options for 5 lug.. thats really the biggest reason I think people swap them. Check out The Little Shop in Nashville for your brakes, drop kit, 5 or 6 lug conversion spindles. They'll have anything you need

Hope this helps!

[raggedjim]

Originally Posted by JWQ

Thanks for the information, also I saw a Youtube video that said the 73-87 front spindles would bolt into the stock 70 front a frames , does anyone know for sure?

The spindles will fit if you change out the upper and lower balljoints and the tierod ends.

[JWQ]

Thank You Guys for all the feedback ! I restored a 1972 Nova about 25 years ago and relied on feedback from forums to complete that task. A lot of knowledge from experienced guys who gladly share their knowledge to help others !!

[cj847]

Here is the guide for the front disc options. Scroll down to brakes. Tons of info.

https://67-72chevytrucks.com/vboard/...d.php?t=646002

[dmjlambert]

I converted to 71-72 manual disc brakes and 5-lug. I recommend it. I took my time and it came out great. The only conversion parts I ended up using are rear axle shafts and the tube brackets for the front hoses. I ended up using OEM truck rally wheels. I recommend the manual brakes.

I bought bearings at NAPA, where it was recommended in a forum post to get the premium ones and not opt for the economy ones, which they also have.

Most special tools such as rear bearing and seal remover, installer, slide hammer, ball joint press, pickle fork were rented for free with deposit from my local car parts store. A couple of inexpensive special tools I got from Harbor freight, a pitman arm puller and this style ball joint separator, which helped with the separation of tie rods.



My journey with a lot of great guidance from forum members here:
https://67-72chevytrucks.com/vboard/...d.php?t=824884
https://67-72chevytrucks.com/vboard/...d.php?t=841065