I have a 94 SR5 with automatic transmission. When I start up the truck cold, and put it in gear either reverse or drive. I get a HUGE flex from the rear end. It feels like the it lifts up about 2 inches in the rear. I'm thinking the springs are broken or shot!
My question is, what are the years for replacement? Also will 4 runner springs work and would they be a little heavier?
Thanks for any input.

 

has anyone observed the lifting of the rear of your truck or it just something you're feeling inside? does it lift one side more than the other? does your truck sit level or does it have "butt sag"? butt sag is a pretty good indicator your leafs are worn out - many toyotas get this over time. if you have a broken leaf spring you will definitely know immediately that there is a problem because you'll be riding on the bump stop. what you've described sounds more like the shocks aren't doing their job and are not dampening the torque twist of your drivetrain - how old are your shocks and what is the condition of the upper and lower shock mounts? i believe the test of shocks is to rock the body of your vehicle and see how long it takes the shocks to stop the rocking, or something to that effect. it could be something as simple as replacing your shocks, but we won't know until you diagnose.

as for replacing the leafs you have to get them off a pickup. all 1990+ 4runners came with coil sprung rear ends, so that won't help you at all. you could probably swap leafs off a 1st gen 4runner or an earlier model pickup, but you'll have to check the lengths between the models (search here, google, wikipedia, etc). easiest swap would be a direct swap from another 3rd gen pickup (89-95). other fixes are: add-a-leaf, ZUK coil mod, brand new aftermarket leafs, hybrid leaf packs, and leafs off other years.

 

1st gen runner and 2nd gen pickup leafs are 48', Yours are 51"

I think we need a video of this lifting action.

 

That's a big leaf!

 

Haha yup. Slight frame extension required. Haha. Good catch.

 

Sorry, kinda had to.

 

No not just one side or the other, it's both sides. I replaced the shocks when I got the truck 2 months ago. Also there is powdery rust coming out from between the lower leafs close to the differential, like the springs are doing a lot of sliding and rubbing together.. I'm wondering if the spring bolts are broken?

 

Have someone stand on the back bumper and jump up and down while you look under and see whats moving that shouldnt be!......if it was winter I would say your tires are freezing to the ground....LOL....have you tried brake torquing it in reverse to see if you can figure out whats moving.

 

That's how us 1st gen Runners roll. Try not be jealous.

I second the request for video of the rear flexing. I'm having a hard time picturing it.

 

so if you put in in drive when its cold does it squat?