60 series front axle on a 40 using rear spring hangers? (2 Viewers)

[Chamba]

Has anyone out there swapped a 60 series front axle onto their 40 using a set of the spring hangers from the front of the rear springs? I note that they place the spring about 1.5" outside of the frame and may be a good match for the wider axle.

Does anyone know for certain whether this will work? I have access to plenty of the hangers, so I can do the swap easily enough if the width will be right. Then I can just use some tubing stock to make off-set rear hangers for the shackles.

Thoughts from the metal-fab gurus? Comments? It seems a pretty easy way to make the axle work and to reverse the shackles. I already have the rear 60 series axle installed, and now I'm wearing out my front tires very quickly.

Cheers,

Josh

 

[lcwizard]

Why are you wearing out your tires quickly? The 60 rear is closer in width to a 40 disc brake front end than a 40 rear is. Is this a spring under or over?

 

[Toshi38]

there are a few pictures floating around of people doing something like that with some nice big gussets.....

I almost did the same thing when I did my spring over but instead ended up putting 70 series axles in (I picked them up cheap) and I simply moved the perches since I was doing a soa anyway!

 

[Chamba]

Why are you wearing out your tires quickly? The 60 rear is closer in width to a 40 disc brake front end than a 40 rear is. Is this a spring under or over?

I don't know. I had it aligned, and the aligment guy thought it was because the rear track width was 2" wider than the front. My alignment was spot on and the rig handle great with the wider rear axle. I'd like to leave it, but the tires are just getting destroyed on the outside; as if it had a really bad toe-in. The rig is OME spring under with 33 x 10.50x15 BFG A/Ts, factory power steering and a winch.

After the new alignment I rotated the tires and put the never-used spare on. With just-over 1,000 miles on the new tire up front, it is wearing very obviously on the outside.

I want to use the factory hanger because I don't have access to a good fabricator down here and I don't own a welder (although I can weld fairly well). I can rent a welder for a day to mount the factory hangers and shackle mount, but I don't think I can fabricate and then weld up the hangers in one day.

Cheers,

Josh

 

[broth9640]

Ask OilHammer about it. I cant seem to find his build thread, but he did 70 series axles under his 40 and moved the perches. Not sure how he did that? It seems like you should be able to use the 40 perches, but I have no experience with it. OilHammer did a complete drive train swap and 3BT diesel into his 40. Send him a PM

 

[Fast Eddy]

I had it aligned, and the aligment guy thought it was because the rear track width was 2" wider than the front. My alignment was spot on and the rig handle great with the wider rear axle. I'd like to leave it, but the tires are just getting destroyed on the outside; as if it had a really bad toe-in.

These statements add up to a bad alignment guy. The toe-in is probably "really bad".

A wide rear track will have no effect on tire wear, even if it was a foot wider on either side.

Do a search and check the toe-in yourself. It doesn't make sense to pay an alignment guy to work on a '40. There's only one setting and it's easy to do in the driveway if you have _any_ skills.

 

[Toshi38]

I agree that its an alignment issue. I have 70 series axles swapped under my truck as well ....

Time to get out your measuring tape...


Did you get a 2 wheel alignment or a 4wheel alignment?

If you just had a 2wheel one done I'd check out a place that can do it on all 4 wheels and ensure that you actually have the rear correct

 

[Chamba]

They did a 4 wheel alignment. Thing is, it was wearing before the alignment (which is why I brought it in). I measured it on my garage floor and it looked perfect, so I thought I must not be able to tell the angle well with just a tape measure.

When I brought it in, they did a 4 wheel alignment and he asked me if I knew that my rear track width was 2" wider than the front; of course I did. He then said that the alignment was good (even slightly toe-OUT) and that he moved it slightly.

Since then, my front tire have continued to wear just like before, but only on the outside. The inside still looks brand new and even still has the little nubs still there (the tires only have about 3000 miles on them).

Any other thoughts on what could cause this? I agree that a 40 is a simple creature when it comes to alignment.

I rebuilt the trunions about 3 years ago and had to replace one of the housings because the PO must have mislaid the metric bolt and had used a standard 1/2" bolt and an impact wrench to hold the calliper on Could this cause it? I can't see how.

I'll PM oilhammer - I remember his build; 13bt with 70 series axles and lockers if I remember it correctly - very nice.

Cheers,

Josh

 

[Toshi38]

Are you wearing front and rear or just front?

Do you know what your caster #'s are?

Putting a 60 axle in the front would possibly solve this problem... but not because of the difference in track width. Probably just because a different axle would fix your issue that's currently causing the tires to wear incorrectly.

To answer your original question I think you could use the 40 series spring hangers without issue although you will want to gusset them for sure and possibly have to move the tab that normally welds to the frame. Are you planning to keep your current leaf packs or change those to 60 ones as well?

 

[Chamba]

I don't know the caster #s, but I'm sure I can find them on the print out. I'm sort of thinking the same thing as you about replacing the front axle - it will fix it no matter how. It is only wearing the front tires, not the rears at all. When I rotated the rear to the front, it looked brand new (for about a week, then it started to get chewed up).

I'm planning to keep the 40 series OME front springs. I just PMd with Chicago a few times about his project, and I reckon I will not do the shackle reversal. My rig handles beautifully as it is now (it only has 75,000 miles from new), has factory power steering and does not wander at all. Thus, I think I will simply gusset the frame and move the hangers out 1.5" per side with the shackles staying up front.

I am thinking I will move the spring forward 1" though to increase the wheel base. I moved the rear axle back 2" when I put the 60 series axle in and it made a world of difference in how it rides. So if I move the front forward an inch, then I'll wind up with a 93" wheelbase, which may be pretty good.

Cheers,

Josh

 

[chicago]

Josh...
Here are a couple shots of my front gussets for my hangers. Just cut some 2x4 tubing to match the angle and welded it in. Used a 3/16 in plate as a scab plate on the frame. Again...ruff stuff is where I got the SOA "KIT", but you can get individual parts from the kit.

 

[Chamba]

Josh...
Here are a couple shots of my front gussets for my hangers. Just cut some 2x4 tubing to match the angle and welded it in. Used a 3/16 in plate as a scab plate on the frame. Again...ruff stuff is where I got the SOA "KIT", but you can get individual parts from the kit.

Wow, those gussets are beautiful!

Josh

 

[Chamba]

I just bought a complete front axle out of an '89 HJ61 (same as an FJ61 but with a 12ht), so I will let y'all know how the swap goes.

I'm going to put my front cable locker third member in this new axle, so I need to get a Longfield birfield with the 4 1/4" splines to accomodate it and then grind out the little oval to fit the locker.

Does anyone have one they would want to trade for a 40 series Longfield? I bought one of those before realising that my 40 series axle was chewing up my front tires. I sure waste a lot of money....

Josh