4runner rear flex and diff swap

[custom hauler]

hey guys ive just recently bought myself a yota. been on this site a while and previously owned a range rover. but dw ive woken up to myself and bought a real truck lol

ok wat i bought is a 1989 2door 4runner sport. this sgape was mainly a 4door model but i managed to get a 2door at a good price.

its got an ifs front with a coily rear end.......

so far i have extended the rear arms to achieve more flex......ive moved the lower arm mounts on the chassis forward to the front of the truck 230mm and fitted factory 80's lower control arms......with the tops ive removed both arms and brackets and i am using one of the original lower arms in the top for extra length. ive mounted it just slightl offset to the centre so it doesnt clash with the tail shaft....i will be running 14 inch travel shocks ( not yet fitted ).

now im hoping fingers crossed that it will achieve sum fairly big angles with this set up......

as for the front ive managed to find a cheap 80's front diff housing and centre. im not quite up to the stage of installing that yet but its on the list to do......... now my dramer is i was told that an 80's front track was only 2 inchs wider then an ifs rear track. but since ive measured it after following my friends word on the size it turns out to be 5 inchs wider.

was wondering if there is any way of reducing the track on the 80 front to get it sumwat closer to the ifs rear?????

and ive been lookin in a few mags and all the pics with 80's flexed up dont seem to ave a very big amount of movement in the front end.

how can i achieve more flex in the front but retaining the radius arms in the front???

any feedback or advice would be greatly appreciated.
cheers sam

[Struth]

What do you want to do with the car,

I have 80s front set up and 80s rear lower arms with standard top arms, it flex's well enough for me, ditch the 80 front diff and get a 60 to get the same track width.



[/quote]


No comp flex there for sure, but as a weekender it goes pretty well.

Some spacers between the castor plates and castor bushs help with flex compared to a standard 80, as does having the RAs only spaced apart the width of a 4 Runner chassis vs the width of an 80.

Cheers

[Mr DJ]

Struth's 60 front diff has a stronger centre being 9", tho I went for a Bundera front cut and had that put in the front.
Same 80 HP front diff centre but narrower (same as leaf hilux width) so with IFS front hubs + rotor spacers the track matches.
Custom front radius arms (with bush set out same as factory 80 series arms) but shaped slightly different to allow steering rod to remain behind the diff.
Definately no travel ramp queen but flexes ok for tourer & weekend trips.



If I was to do it all again, would use a late 75 series or 78/79 series cruiser front diff, same centre but has the bigger CV's/axles same as 80 series. Have not measured one but width seems to be good to suit Hilux/4Runner.

[timbotim1003]

Hey guys, I just wanna let you guys know that if your running factory upper arms and longer lower arms on your 4runners or surf, is to keep and eye on the factory welds holding the cross members and controle arm mounts,
when i chopped my truck in half i found they had all cracked and breaking away from the chassie rails due to the short urms up top and a flexy rear end.
I cut them all out and put new ones in.

[custom hauler]

thanx for the feed back guys

Struth; i think ill be sticking to the 80's front because i like the idea of having the same size centres front and rear. i think i can get the to wheel tracks to be close buy running different offset wheels from front to rear. i know the 60's is a stronger diff due to it being a 1 1/2inchs bigger centre but ive got the extreme magazine at home that features ur car and i dont think im quite up for the amount of work u went to to get the 60 under the front of urs. let alone the rear to match the front.
like MR DJ said the landcruiser series of the 8 inch diff has larger cv's and knuckles to handle the stress. the truck wont be turning anything bigger than a 35 and thats only a maybe im quite happy with the performance of the 33's on it.

sum progress in the rear with good results 2day though. i managed to get the motor running right again so i could flex it up on the garden bed out the front of my joint.

i managed to pull 800mm of wheel travel out of the rear end with the front wheels still touching the ground ( was quite surprised at how level the car was sitting.

i stopped at 800mm because the car ramp i had ontop of the garden bed to get a bit more lift started to slip towards the edge and i was worried about destroying the sill.

i think if i narrow the upper arm link ends so the bushing hangs out a lil wider so it can twist abit more i might ba able 2 achieve 1000mm of wheel travel in the rear.

so once i do the sas in the front and hopefully make that flex fairly well it should be a pretty capable rig..

next on the list is a engine conversion. i realy need sum more ponys in this thing. the lil 22r just aint cutting the mustard anymore lol

cheers sam

[Struth]

If I was to do it all again, would use a late 75 series or 78/79 series cruiser front diff, same centre but has the bigger CV's/axles same as 80 series. Have not measured one but width seems to be good to suit Hilux/4Runner.

I didn't know the 70s had better CVs, will remember that for next time

[Struth]

Hey guys, I just wanna let you guys know that if your running factory upper arms and longer lower arms on your 4runners or surf, is to keep and eye on the factory welds holding the cross members and controle arm mounts,
when i chopped my truck in half i found they had all cracked and breaking away from the chassie rails due to the short urms up top and a flexy rear end.
I cut them all out and put new ones in.

Will do, thanks

[timbotim1003]

I wouldn't worry bout wheel track too much , as long its close.
Your right bout the 80 cv's and balls but ide still gor for the 60 diff, its easer to get parts and cheaper too, especally out at a 4wd park, if you break one, put a lux one in.
put a set of longfilds in and its almost as tough as it gets.

I run a 60 diff up front with leaf springs, 14 inch shocks
and a nissan gq rear diff with coils, 18 inch shocks and it flexes bout 1300mm.