60 springs on fj40 SUA - photos please

[Mustangstolli]

Hi
Due to local regulations, I'm looking at putting fj60 rear springs on my 40 series (front and rear) SUA (I know there should be an O in there but there isn't!)

I do not want to trim the tub much, so looking at putting the short length to chassis and redrill the perches to try to keep wheelbase close to factory. (I know this is hardcore corner, but I didn't get many replies in 40 series tech).

Anyone who has done something similar please post some photos.

How much lift can I expect with the standard 60 series springs?

I'm looking at using later model 40 series hangers so that pin diameters line up with the 60 series, and rotate rear shackles hanger 180deg and make longer shackles.

What should I do with the front shackle hanger? Will I end up with a ridiculous shackle length to make it work? Don't want to do shackle reversal on front as I'm staying SUA. Might have to re-arch springs for the front and even up height with longer shackles on the rear.

Mainly after more droop/flex and a smoother ride.

Thanks for any advice/photos!

 

[Josie'sLandCruiser]

Hi all,

IIRC the front 60 Series leaf springs are not much longer than front 40/45 Series front springs, so you are probably good there.

The rear 60 Series springs are definitely longer than rear 40 Series leaf springs. If you want to use these without moving the rear axle farther back consider re-mounting the fixed-end mount of the rear springs. Mount the spring pack onto the rear axle tube, center the axle in the rear fender well, then mark where the fixed and shackle mounts need to go.

Good luck!

Alan

 

[Fast Eddy]

If you don't move the fixed mount in the rear you'll move the axle back about 65mm.

I have heard that fj62 springs are a bit more flexible. Not sure if it's true. They have more, thinner leaves. I can attest that they are nice and flexy.

The front is going to be a different story. You're going to have to move the fixed end of the spring. I don't think I've seen anyone who did it, so you'll be on your own to a certain extent.

Try to keep all the bushings the same if you can. If you plan it out right, you can use the same shackles too. Plan for really long shackles with 40 degrees or so with the weight on. It will flex great.

 

[Mustangstolli]

Hi
Thanks for the responses. I believe you are correct with the 65mm extra diff movement to the rear. I was hoping to redrill the perches and gain 30mm or so of that back. Trimming a small amount of the tub will be ok I guess - rather than moving the perch forward. How many leaves would you recommend (I won't be carrying much weight at all).

I was going to use 60 series rears on the front as well. With the front I don't want to move the perch back as I'll start affecting castor in weird ways. Moving the front diff forward 30mm or so should be ok - maybe need to trim the front lip of the guard. Just not sure with the length of shackles I'll need whether they'll dig into obstacles too much.

Some photos would be great if anyone has gone down this road before!

 

[Mustangstolli]

I might have to just do the rear if the front hangs too far forward.

 

[sadam_husain]

haven't had any experience with 60 series springs but I got quite good results with 70 series front springs in both ends of my truck, they were about 30mm longer than the Lovell springs that were in there so the shackle angles flattened out and gives a lot of swing back and down travel, I had to lower the front bumpstops about 50mm and the rear 40mm so I don't get a huge amount of up travel and smack the bumpstops a fair bit, I had to redrill the perches at either end as the centre bolts lined up in different places. Had to put long travel shocks in and long brake hoses.

 

[cruiserpilot]

I put 60 series springs on the rear of my 40, they are about 4" longer. It effectively moved the axle back about 2". For looks, it seems better to me as I always thought the rear tire too close to the body, (and I run 38.5" TSL/SX's on SOA.) even with SUA set-up. I left the front spring hanger stock, but I punched out the rivets on the rear and just flipped the hanger around, lined up the holes and welded it back on. I have nice shackle angle at the rear and a much better ride/flex.

I don't have any close up pics, just this one of the pack waiting to go for a walk.

 

[Mustangstolli]

From memory, the 70 series front springs are about 15mm longer (along the length of spring - not eye to eye) than standard 40 series springs. Was your 30mm measured eye to eye? Were the lovells springs re-arched?

What was the reason for extending the bump stops - purely due to the size of tyres and preventing them hitting the body?

By re-drilling the perches did you keep the "factory" wheelbase?

haven't had any experience with 60 series springs but I got quite good results with 70 series front springs in both ends of my truck, they were about 30mm longer than the Lovell springs that were in there so the shackle angles flattened out and gives a lot of swing back and down travel, I had to lower the front bumpstops about 50mm and the rear 40mm so I don't get a huge amount of up travel and smack the bumpstops a fair bit, I had to redrill the perches at either end as the centre bolts lined up in different places. Had to put long travel shocks in and long brake hoses.

 

[Mustangstolli]

I take it you kept the short end of the 60 series spring to the chassis if it extended the wheelbase by 2"?

Did you manage to take a few measurements of centre of wheel/centre of opening before and after the spring swap? I take it with the size of your rubber you have trimmed the tub substantially? The wheel definately looks centered in your wheel opening!

Does the position of the wheel change much going SUA to SOA? With the flatter spring it'd probably move the wheel further towards the rear if anything?

I put 60 series springs on the rear of my 40, they are about 4" longer. It effectively moved the axle back about 2". For looks, it seems better to me as I always thought the rear tire too close to the body, (and I run 38.5" TSL/SX's on SOA.) even with SUA set-up. I left the front spring hanger stock, but I punched out the rivets on the rear and just flipped the hanger around, lined up the holes and welded it back on. I have nice shackle angle at the rear and a much better ride/flex.

I don't have any close up pics, just this one of the pack waiting to go for a walk.

View attachment 837057

 

[cruiserpilot]

The leading edge of the wheel opening is stock. Those are the Bushwacker flares. I cut 1" along the top, and it goes to about 2" off the rear of the wheel well opening. Really not that much of removal of metal.
I am really happy with the axle position.

 

[Mustangstolli]

Did you fold the metal over to form a lip - or is it rigid enough with the bushwacker flares?

 

[cruiserpilot]

I left it cut, I didn't roll it. Along the top edge it is only an inch or so from the wheel well.

 

[cruiserpilot]

I have a photo from the restoration here showing the cut without the flares. Now the black sharpie pen line is the outline of the bushwacker flare that I removed.
As you can see the front edge is stock quite a ways up, and then I made a fairly crude straight cut for the flares. If you notice, the fender flare line is just below the exposed spot welds. I guess one day I should do a thread on this whole thing. I cut the front edge of the rear fender off to get at the spar, I wanted to see inside it for rust, but that whole piece was stock in shape.

 

[Mustangstolli]

I can sorta see where the standard opening finished - approx 4" lower than the top cut? Looks like its opened up pretty much to the top of the wheel well.

Getting the bushwacker flares shipped to Australia is the $$$ exercise. I have a set of tj flares in the shed, but unless I use my massive offset 35" muddies it will look strange. That's what I'm trying to balance - minimal cutting so I can still use 32" or 33" tyres for majority of driving, but also be able to squeeze in 35" with extended bumps stops when I need to get thru heavy rutted terrain.

 

[Mustangstolli]

Just had a look at my tub and there's only 2-3" of material before the top of the wheel well.
So you'd have 1 or 2" of material left?
Looks like the tub has been opened up quite a bit to fit that rubber in!
I guess that's the soa clearance.
Measured centre of wheel opening and centre of tyre - there's probably less than 10mm in it, but the tyre does seem to sit slightly forward in the opening.

 

[cruiserpilot]

Still was 1 1/2" of material left above the tire. It looks a lot larger of an opening than it was.
If you see, I wrote the measurements on the tub, you can copy them and mark it on yours for comparison.
Too bad it is so expensive to ship stuff, I know.

 

[sadam_husain]

From memory, the 70 series front springs are about 15mm longer (along the length of spring - not eye to eye) than standard 40 series springs. Was your 30mm measured eye to eye? Were the lovells springs re-arched?

What was the reason for extending the bump stops - purely due to the size of tyres and preventing them hitting the body?

By re-drilling the perches did you keep the "factory" wheelbase?

I don't know what the extra length worked out according to some spec's I found on the net my 70 series springs should have been 15mm longer than stock 40 series springs, you can see the difference in the 3 different sets of front springs I've used

1st pic, left= 70 series old man emu, middle= lovell, right= 40 series old man emu,

2nd pic, top= 40 series old man emu, middle= lovell, bottom= 70 series old man emu

the wheelbase has changed and pushed it out either end slightly but not enough to affect driveshaft lengths etc

bottom pic shows the wheelbase

 

[Mustangstolli]

Looks like the Lovells springs are re-arched 40 series springs - you certainly lost a lot of length "eye to eye" in order to get the height increase!

The 70 series springs look like the perfect option if you want extra height without sacrificing spring length!

From the photos it looks like the "unloaded" 70 series springs are about 1.5" to 2" higher than the standard 40 series springs. Do you know how much lift you got from the 70 series compared to stock?

I'm starting to think this would be the best option for the front! it'd be good to know what the shackle eye to pin and pin to fixed eye distances are! Did you take out any leaves from the 70s packs when you installed them?

What size rubber are you running? They look like 35"?

 

[sadam_husain]

I only tried the 70 series springs after I broke both front springs and happened to have a spare set of 50mm lift Old Man Emu front springs sitting in the shed, it was going to cost me nothing other than a bit of time to try it out, I did the front first coz I only had 1 pair of springs. Other than re-drilling the perches they bolted straight in, coz of the different location of the centre bolt I had to re-drill right up at the front of the perch but still had enough meat left to prevent it ripping out, at the same time I was limited how much I could shift the axle forward so my tierod and drag link didn't fowl on each other (I've got a 70 series steering box up on the front of the chassis rail). My cruiser's an 83 model so it users the same 18mm pins and shackles as a 70 series cruiser. The shackle angle came out at about 45 degrees sitting idle, this left me with just enough up travel on spring compression and mostly down travel with the springs opening right up with the amount of back swing on the shackle, I also had a set of Old Man Emu shocks sitting in the shed with 10" travel and they use the full travel on the truck, they are fully extended on down travel and fully compressed where I lowered the bumpstops to. I had to put a long brake hose on and dropped the bump stops by 50mm. The front ended up with a significant lift from what it was, I cant tell you how much from stock but I probably ended up with 4" from what I had. I ended up putting a matching set of springs (also 70 series front) into the rear of the truck and achieved a similar result, I didn't get the same amount of articulation as the front but I got a significant increase from what I had and a slight lift probably about 1 1/2" from the lovell springs I took out of the back. I didn't have to play around with my driveshaft lengths, both axles got pushed out slightly but there was plenty of length left on the slip joints.

Over all what I achieved is a truck lifted enough at both ends to get some reasonable sized tyres under it (measure 35.6") and a flexy truck that now articulates and doesn't ride as stiff as a surfboard, I used to constantly be clicking the diff locks in and out to maintain traction coz I always had wheels lifting off the ground and now I can drive over most stuff without needing to use them.

Its an easy swap to do without having to modify anything serious but be aware you limit your up travel, have increased body roll and end up with pretty flat shackle angles

 

[OilHammer]

I was thinking that 40 series front springs were flatter than the rears. If you put 70 series front springs on both ends, wouldn't that change the rear's lift?