my rear end, comments please

[bad_religion_au]

Fj40, rear springs are stuffed.

grafting on fj55 rear springs, 3.5 inches longer (eye of the spring to spring perch is where teh extra length is)

measured up, if i move my axle back3.5 inches, diff pumpkin will hit the gas tank.

so,

there are 3 bolts/ rivets on the bottom of the chassis rails, which hold on the solid spring mount (not shackle mount) 1.5 inches apart, so if i remove these rivets, make the further most hole on the spring hanger line up with the middle hole in the chassis, redrill the front hole, effectively moving the spring mount 1.5 inches forward.

this only moves the axle back 2 inches once the 55 series springs go in.

this will clear gas tank.

rear shackles are vertical now, so the 2 inches further back will make them out to about45 degrees, so no prob there. no problem trimming the guards behind the wheel. the trimming in front of the wheel may allow for 35's once the axle is moved back 2 inches.

the front driveshaft on the 55 series is 1.5 inches longer than the rear shaft already in the rear of the 40, so i could use that untill i get my other one retubed/ lengthened, and the slip joint in the middle of the shaft should be able to cope with the extra .5 inch length.

bolting the front spring hangers on with strong bolts. i have read alot of US sites, SAE grade 8 sounds like the go, do we have the same bolt ratings?, if not, what is our equivelent bolt strength, so i know what to ask for at the bolt place.

new bushings, spring pins, u bolts etc is a given.

the spring clamps were buggered during the pulling apart of the springs, the plan is to get 4 mill thick box section, 75mm x 75mm, cut the top off it, making a U shape, to use to locate the spring (stop it splaying sideways). a hole will be drilled at the top of this, and a bolt/ pin used to limit spring separation onroad.

exaust should clear, if not, i'll cut it off behind the muffler, and have it exit into the wheel wells, or move the mount in a bit, it'll clear.

anything i have forgotten, this is my only car/ DD so i really want to plan for most eventualities, and this is the first time i am doing anything more than putting part A where part A should go.

will be away for a couple of days, so don't think i'm being rude by not answering...

 

[73lndcrsr]

that all sounds good.

For the bolt equivalent, I think 10.8 is what you need in Metric.

 

[bad_religion_au]

yeah, the bolt equivelent isn' too important (cut and paste from the messagei put on an aussie site.) i have seen grade 8 bolts around, so that part was more for the aussies.

 

[RUSH55]

Why go thru the trouble of drilling and bolting? Why not just weld it and be done?

 

[Jman]

"Do these springs make my ass look big?"

 

[IDave]

Pics Please!





























Wait. No. Forget it.

 

[largenfirm]

Is there any reason to actually cut the top off the steel box to make it u-shaped?

Kirk

[Oh, and "those springs absolutely don't make your rear-end look big" - you see, I've been married twenty years to a fat-bottomed girl, and have the scars to prove it ]

 

[theo]

My exhaust exits in front of the rear tires and I get fumes with the top off. This bites the big one. I would try to rig the tailpipe to exit in the stock location.

 

[srafj40]

"Do these springs make my ass look big?"

Hehe

No, no... that would be yer big a$$ that makes yer a$$ look big

 

[bad_religion_au]

Is there any reason to actually cut the top off the steel box to make it u-shaped?

Kirk

[Oh, and "those springs absolutely don't make your rear-end look big" - you see, I've been married twenty years to a fat-bottomed girl, and have the scars to prove it ]

yeah, if i make it U shaped, and bolt through the top, i can remove the bolt for a little more flex... also 45's have the U with a bolt standard, and i don't want to make it obvious that it's modified... cops hate modded 4x4's in australia


that is the same reason i'm not welding the spring hangers 1: want it to be able to be reversable, as wheelbase changes are illegal, and impossible to engineer in australia, so if the sh!t hits the fan, i can at least reverse the proceedure.

also i don't have a welder and my welding skills are sh!t.

and i was told not to weld the frame too much, makes the metal brittle i have been told

 

[RUSH55]

Welding to the frame is fine. The FJ55 front shackle hangers come welded from the factory. I have read a couple of posts (one by Woody) where the rivets were ground off and removed, then moving the spring hanger moved one hole then drilling a new one and bolting it back on; but I've always wondered, if you're gonna bolt it, how do you get the nut in the frame? Are'nt 40 frames fully boxed at the area of the spring hanger?

 

[hammerhead]

Yes, 40 frames are boxed, but I've been able to get nuts in through the holes on the inside. Can be fun though...

 

[RUSH55]

So then how do you hold the nuts in place? Drill access holes big enough to fit a wrench-head in?

 

[bad_religion_au]

was thinking a socket with breaker bar through the hole in the side (hwere i am drilling will line up perfecly with a hole).

another forum i have mentioned this on brought up the possibility of cracking the frame due to a change in load points on the chassis. being that it is using 2/3 original holes, is it probable this will be an issue?

 

[s79bj40]

its always possible, especially if you are carrying huge loads over the canning, or something like. But for normal driving and remembering its a cruiser and not a jeep or terrorcan, i wouldn't see it as being a huge problem.

 

[hammerhead]

another forum i have mentioned this on brought up the possibility of cracking the frame due to a change in load points on the chassis. being that it is using 2/3 original holes, is it probable this will be an issue?

Dude, don't overthink this. Move the spring hanger the way you mentioned at the start of this thread. If drilling a hole in your framerail will make it crack then why does the factory drill holes in the rail. Moving the hanger that small amount couldn't change the stresses involved that much. Besides, many of us have drilled holes and moved perches etc.etc. without problems...

 

[bad_religion_au]

thnx hammerhead... this is what i needed to hear LAST NIGHT before i went around looking at options (hence the other 2 posts started in quick successions), but i think i like the redrilling of the spring perches better, if i can manage to get 1.5 inches out of them, spring perches are easier (mentally anyway) to drill into than the frame... namely cause i can get perches for 20 bucks if i stuff it, and i have a spare rear axle (complete with perches) sitting out the back anyway...