40 series diff swap

[bj 666]

ok plan is to remove stuffed 40s diffs and replace with nice shiny 80s diffs i just happen to have lying around. the new diffs have all coil spring, control arm mounts etc removed so ready for leaf spring plates/mounts.

Question is do i go SOA or SUA? if i go soa i only need a high steer arm like the jmac ones ppl have on their 80s.
OR if i go sua then i will need custom steering arms both sides and the tie rod will need to be moved to in front of diff.

Car is basically stock '79 40 series atm. i really dont want to lift it more than 4'' maybe 5'' MAX. so to do soa i would need some flat springs to keep the height down. maybe flat 60s springs, longer and better flex. ideally (sp?) i want to fit 35"s with the min amount of lift so trimming guards for sure and hope too move rear diff back to extend wheelbase also. Car is daily driver with 'B' diesel 'power'plant so driving slow is not an issue (or possible).

so what does everyone think? Yes i could have done other diffs which would have been easier or whatever but this is what i have so its what im doing.
also ideas on where to get stuff done and get arms made and all that. (somewhere in sydney)

cheers

[v840]

If you are going to the trouble and expense of putting 80s diffs under your truck, why not just go coils? Heaps better ride and probably easier to flex up too.
If you are definitely going to go leaves I would go the SOA. Heaps better offroad, arguably better on road (when done right), and you will fit 35s very easily.
Talk to either Overkill Eng. (9476 6137) , Offroad Industries (97487 1116)
or Pro 4x4 (9938 6200). All these guys can help.

[big bundy]

check out daz's truck on www.3rdrock4x4.com, http://www.3rdrock4x4.com/forum/viewtop ... 10&start=0
very tough truck with the 80 diffs under it

greg

[65Mog]

J Mac have done a few of these conversions, 9671 5800.

[bj 666]

ill definately go with leaves. keeping standard fronts with a leaf or two removed to flatten them out. then flipped rear hanger with stock height 60s rears with a leaf(s) removed out the back. will be using standard length shackles.

aiming to run 35"s with the truck as low c.o.g. as possible. hoping that the lift will only be about 4" with flat springs plus whatever is in the tyres. will also do power steer as well.

thinking of doing front shackle reversal also but is it really worth it? there are so many differing opinions on it!

[DIRTY ROCK STAR]

Also, scotto on 3rdrock has just done 80 diffs too.

I dont want to sound harsh but running 80s under it on leaves sounds like a shit idea??
I will trade you my 40 diffs, and i will chuck in some spacers and trade you for 80 diffs. be easier for you with rego, just remove spacers....

[Tiny]

I am on the fence with this one, while on one habd I would say you have 80 diffs, spend the extra$$ and time on a good coil set up, I also say that the front in particular on a 40 can flex very well, and its a set up you know and the time and cost given the 80 diffs are bare by sticking with leaves is a better quicker option.

I would definatly go spring over thoug, it would be tragit to spend the coin and time and stay SPUA

[slosh]

My lux has 80 duffs, IFS rears up front, standard shackles, 35's. They aren't even soft leaf packs- truck handles like it's on rails on the road.
Coils might give softer ride but there is no 80 I've seen flex like this.

[big bundy]

daz's truck flexing on coils, go the coils man, do it, do it

http://www.3rdrock4x4.com/forum/download.php?id=1623

[kroozer91]

Coils might give softer ride but there is no 80 I've seen flex like this.

i have seen better



keep the coils if you are going to the touble and time of putting them under the 40

[Tiny]

Coils might give softer ride but there is no 80 I've seen flex like this.

i have seen better



keep the coils if you are going to the touble and time of putting them under the 40

meh .....soft

[slosh]

Awesome flex there kroozer91. I would have 5 link anyday over leafs, but I was comparing my setup to the radius arms.

If you have the ability to setup a 5 link that behaves on the road and you can get it engineered then that's the way to go for sure.

[kroozer91]

Coils might give softer ride but there is no 80 I've seen flex like this.

i have seen better



keep the coils if you are going to the touble and time of putting them under the 40

meh .....soft

not as soft as some


ps its not my cruiser although i wished it was

yeh 5 links are great but not so good on road.

[bj 666]

i wish i had coils. they would obviously give a better ride/flex but dont really have the ca$h to go with a coil setup. diffs are bare so much easier to go leaves and by playing with pack config etc. can still flex very well.

daz's truck flex's pretty good and that 80 has some awesome flex.

does jmac do full conversions? i will get power steer done at the same time too. i know jmac has done the high steer arms on a few 80s b4 so im thinking of getting it done there. i remember from reading other threads on the same sort of thing that its best to go there and talk directly cos you prob wont have much luck trying the phone? or am i thinking of someone else?

anyone got 60s rear springs and 6" wide flares they wanna 'lend' me?

[bj 666]

been doing some measuring and thinking and i will need to outboard the front springs. otherwise leafs will have to mount too high up on the centre housing, being that i'm trying to keep this as low as poss.

have many people done this? have pics?

the fixed rear spring hanger is offset and its offset the right amount to be used up front. since i'll have 60s springs at the rear, i'll have to replace the rear hangers anyway so plan is to use the rear fixed hanger up front and make an offset shackle hanger too (obviously).

i dont have the 60s rear springs yet so i'll be searching the wreckers' for some but is it worth re-using the hangers off the 60 or just getting some new ones?