Question About Moving Rear Axle Forward (3 Viewers)

[mjw4]

Hi all,

Just got back from my first trip with the 76 and all was well.

I did notice during compression, the movement of the rear leafs going rearward I would rub on the back side of the wheel well, where the mud flaps attach.

I'm running 35s, with what has to be approximately 4" of lift, and the leaf springs I have are also military wrapped on both ends.

Is flipping them around (front to back) a possibility to move the axle forward somewhere between 1 to 2 inches? Is there a better way?

Thanks

- matt

 

[coldtaco]

Never heard anyone flip a rear leaf spring, only the front. I guess you could try it

 

[mjw4]

I’ve been only seeing it for front leafs as well. Just trying to see if anyone has a solution or if I’ll just have to brute force more room.

 

[AirheadNut]

@Rigster runs some fairly large tires on his HZJ76, he might have some useful info about this.

 

[LDowney]

...

Is flipping them around (front to back) a possibility to move the axle forward somewhere between 1 to 2 inches? Is there a better way?

...

For your consideration, You may want to check your compressed drive shaft length to ensure that it is compatible with the axle being moved forward. If the compressed shaft is too long for the relocated axle, the drive shaft may transfer load into the transfercase from the suspension deflections. This would not be loads that the transfercase is designed for.
If needed, the driveshaft could be shortened to ensure that there is no issue.

 

[Rigster]

Hey Matt,

How did you end up with 4" lift in the rear? Just with springs, or springs and shackles? Whose springs did you end up going with?

It is difficult to compare little differences between cruisers and experiences even when the same products are used. I DO recall when I installed my 2" OME rear leafs and extended shackles on mine, I had to kick the axle forward before it would drop onto the alignment pin on the leafpack. With the extended shackles I used, it will change the geometry of where the axle sits (it will be slightly forward more).

With this setup on mine, I have not had to deal with any rubbing in the rear. Maybe I just got lucky.

As far as reversing the leaf springs? Have not done it. It has been a while for me, but are the loops at each end of the leafs the same size? If so, then it may be possible. I realize it is a ton of work, but you could always try it and see.

 

[mattressking]

Just drill holes in spring perch or get/make offset spring plates. I too have this issue with mine and need to decide my path forward as I don't plan to size down from 35s.

 

[RHINO]

^^ this is how we used to do it, always good for an inch. besides, arent the pins offset from center to the front? so flipping them would set the axle even further back?

 

[dogfishlake]

Just drill holes in spring perch or get/make offset spring plates. I too have this issue with mine and need to decide my path forward as I don't plan to size down from 35s.

Agreed. Change the pin locating hole and move axle forward.
Don't forget to pull the zerk out of your driveshaft so it doesn't hydrolock as you move things forward. Ask me how I know!

 

[sadam_husain]

As above I redrilled my perches and spring/U-Bolt plates, I actually did it on my 40 series not my 70 series, I put 70 front springs into both ends of my fj40 to get better height and articulation from the slightly longer springs and just redrilled the perches and bottom plates to get correct axle alignment, I've got recessed bottom plates and they redrilled nice and tidy

 

[mjw4]

For your consideration, You may want to check your compressed drive shaft length to ensure that it is compatible with the axle being moved forward. If the compressed shaft is too long for the relocated axle, the drive shaft may transfer load into the transfercase from the suspension deflections. This would not be loads that the transfercase is designed for.
If needed, the driveshaft could be shortened to ensure that there is no issue.

Thanks for the info, I'll have to look into that.

 

[mjw4]

Hey Matt,

How did you end up with 4" lift in the rear? Just with springs, or springs and shackles? Whose springs did you end up going with?

It is difficult to compare little differences between cruisers and experiences even when the same products are used. I DO recall when I installed my 2" OME rear leafs and extended shackles on mine, I had to kick the axle forward before it would drop onto the alignment pin on the leafpack. With the extended shackles I used, it will change the geometry of where the axle sits (it will be slightly forward more).

With this setup on mine, I have not had to deal with any rubbing in the rear. Maybe I just got lucky.

As far as reversing the leaf springs? Have not done it. It has been a while for me, but are the loops at each end of the leafs the same size? If so, then it may be possible. I realize it is a ton of work, but you could always try it and see.

So the truck came with a lift installed by the PO. After looking around I found the exact lift that they used. It's actually only 3", springs only.

I measured the shackles and they are around 90-95mm eye to eye, so stock.

I'll probably look into re-drilling the spring perch and measure the drive shaft length.

I might get some extended shackles eventually to lift up the rear around an inch and some new front coils to match. From what I read on the shocks they seem to be good for up to 6" of lift, so I believe I'll be good with them until they give out, plus they're adjustable.

I'll have a read through your thread again, but if you have a PN for the shackles I'll take that as well.

 

[mjw4]

Agreed. Change the pin locating hole and move axle forward.
Don't forget to pull the zerk out of your driveshaft so it doesn't hydrolock as you move things forward. Ask me how I know!

You mind elaborating on this a bit for me?

 

[dogfishlake]

You mind elaborating on this a bit for me?

On the spring plate, you would just be moving the locating pin hole forward an inch. I haven't done that personally, but it sure looks like there is plenty of room for that. You could get fancy and weld up the old holes, but I doubt you need to.

On the driveshaft, just pull the grease zerk for the splined shaft that connects the front and rear half. if it is full of grease it will prevent the shaft from collapsing when you move forward. On that note, you may have to ensure you have space to spare on the driveshaft to compress it enough once you do move an inch forward.

The splined part of a Cruiser rear driveshaft should be minimally greased so as not to put pressure on the T-case when the suspension is compressed anyway

 

[mjw4]

On the spring plate, you would just be moving the locating pin hole forward an inch. I haven't done that personally, but it sure looks like there is plenty of room for that. You could get fancy and weld up the old holes, but I doubt you need to.

On the driveshaft, just pull the grease zerk for the splined shaft that connects the front and rear half. if it is full of grease it will prevent the shaft from collapsing when you move forward. On that note, you may have to ensure you have space to spare on the driveshaft to compress it enough once you do move an inch forward.

The splined part of a Cruiser rear driveshaft should be minimally greased so as not to put pressure on the T-case when the suspension is compressed anyway

thanks for that insight

 

[Rigster]

So the truck came with a lift installed by the PO. After looking around I found the exact lift that they used. It's actually only 3", springs only.

I measured the shackles and they are around 90-95mm eye to eye, so stock.

I'll probably look into re-drilling the spring perch and measure the drive shaft length.

I might get some extended shackles eventually to lift up the rear around an inch and some new front coils to match. From what I read on the shocks they seem to be good for up to 6" of lift, so I believe I'll be good with them until they give out, plus they're adjustable.

I'll have a read through your thread again, but if you have a PN for the shackles I'll take that as well.

You will need to shop around for some extended shackles for a 1" lift. I had Dan from 4wheelauto get some custom made for me for 2.5 inches of lift, so I would have a slight rake in the rear. (4" lift in front and 4.5" total rear)

In my thread, I think I recall working out how much longer the shackles need to be for each inch of lift in the rear, that should help narrow down your search for the correct length. All the best in your upgrades!

 

[mjw4]

You will need to shop around for some extended shackles for a 1" lift. I had Dan from 4wheelauto get some custom made for me for 2.5 inches of lift, so I would have a slight rake in the rear. (4" lift in front and 4.5" total rear)

In my thread, I think I recall working out how much longer the shackles need to be for each inch of lift in the rear, that should help narrow down your search for the correct length. All the best in your upgrades!

Ya I've read around and the consensus seems to be (total length over stock) / 2 = effective lift. So a shackle 2 inches longer than stock would give around 1 inch of lift.

Doing a quick search I can see a few companies in Australia with 100mm shackles (50mm over stock) for a 25mm lift. But I do like the idea of having slight rake so I may get in contact with Dan and get something similar albeit only 1.5" since my leafs are at 3".

First and foremost is a complete brake refresh, service the knuckles, and install the manual hubs. Might also look at an 80 series booster upgrade.