710m rear springs

[MTPinz]

As it sits, I am at full extension (limiting straps maxed out) when unloaded. With five sandbags and five wheels and tires I gain about an inch of down travel which does wonders for the ride quality and tire geometry.
So adding weight can alleviate the problem but it's a drag when I have to unload everything just so passengers can have a seat.

I've seen other 710's with lots of slack on their rear straps when unloaded so what's going on here? Maybe I have HD springs in the back or something?

[rmel]

If the limit straps are under tension when unloaded there's a problem.

Is this the case for front and rear straps?

Check the length of the Spring Pins. There are several length options
based on the expected weight of a given truck. The longer pins (72mm)
will add a fair amount of lift. Was there a prior owner who wanted to
lift and add oversized tires? Also check the springs, there are 3 spring
stiffness options, although the only one I am aware of available today
is the Mid strength. There should be markings on the springs to denote
the strength.

[MTPinz]

The fronts seems completely normal but yeah, unloaded, I can pluck my rear straps like a guitar string.

I'll check my rear pin lengths and report back. That would be an easy fix if that were the case. The rig didn't come with many PO details so it's a bit of a guess, but there's nothing on it that's too far from stock. We'll see if I can find any markings on the rusty springs too. Thanks rmel!

[Mr Zero]

MTPinz, I shot you a PM regarding a spare set of springs that I have.

[MTPinz]

There were no discerning marks on the rear springs but the spring cup pins measure out to be around 135mm from the top of the bolt to the tip. This seems about right as my spring cups are fairly close to the axle, but that could also be because my cups are severely corroded!
Here's a pic of what I'm working with. The replacement limiting straps are the same length of factory straps I removed...I believe they were 17.5" eye to eye.

IMG_20220302_174839735.jpg (1.34 MiB) Viewed 3648 times

[MTPinz]

I should also note that I'm sitting 1.5" higher in the back vs the front, measured at wheel centerline. That doesn't seem too far out either.

[rmel]

Hmmm, Ah Ha !! Well clearly those aren't OEM limit straps.
Looks like OKoffroad Nylon webbed. For the Pinz, these straps
are sold with a recommended length of 17.5" C-to-C. They can
be ordered to lenght, sooooo....if yours are short they can be
replaced with the recommended 17.5" or if that's too short then
a custom build can be ordered.

Here's a link to their site https://okoffroad.com/stuff-susp-limitingstrap.htm

BTW that duo of garaged Pinzie's is yours truly -- I DO NOT use synthetic straps.
I do get my recovery gear from OK including Ramsey winches. Didn't know this PIX
was on their site in that section

I have included a PIX of my 710K rear end, no significant load in the rig.
Also of note my springs are new, mid-strength. Total of 11 turns.

710-rear.jpg (734.13 KiB) Viewed 3628 times

[MTPinz]

So the OE rear limiting straps were snapped in half when I first got the Pinz, so I went ahead and replaced them with those OKOffroad ones. I verified the length of the old to what OK offered and they were the same. No complaints with them so far, they seem to be doing a fine job.

My Pinz is nowhere near as clean as yours, nor will it ever be lol, but here's a better shot of where I'm at.

IMG_20220303_183613049.jpg (1.65 MiB) Viewed 3595 times

You can see the distance between the bumps and lower cups are greater on mine. It also seems like the coil count is the same...hmmm. You can also see that my lower cups are kaput! But look at that shiny new hardline, oh yeah!

Anyone have any dimensions for 710 spring cup pins? Does 135mm seem about right?

[rmel]

Unlike the front suspension, I don't think there are pin length options
for the rear. Although 135mm seems a bit long? Did OK send you the
proper length straps? With them fully extended should be easy to measure.

[rmel]

Just measured my pin length.

The overall length from tip to the top of Hex is in the ballpark of 135mm.
Seems your pins are normal.

I also measured the total length of the Springs including the top of the cups
and it measures exactly 10". Curious what yours is? Looks more extended.

That leaves the Straps as too short or unusually strong Springs.

[MTPinz]

Great, thanks Ron!

I'm pretty sure my straps are 17.5". I remember double checking before I bolted them up. I'll verify the straps once more as well as the coil spring when I get home later this evening.

Cheers!

[MTPinz]

So the straps are indeed 17.5" eye to eye. The springs, measured from the top of the cup to bottom of the cup come in at 11.5", so 1.5" longer. This would explain the difference in ride height that I'm seeing from front to back.

If my pins are about right, the straps are right, but my springs measure different, that can only mean the springs are too long correct?

Are the springs on a 716 different lengths and swap in? The history is vague on this one so who knows who did what.

This place rocks. Even though it can be slow at times, it's proven itself time and again. Thanks fellas!

[Joeri]

The springs on a 716 are not the same as the diesel pinzgauers have only one big spring in the back as the 710 petrol have 2 small ones... did you check your axles ? Could be a sign of axlewrap , check the lockingbold that prevents the outher axletube rotating on the inneraxletube. If the axle is turned one spring sits higher then the other spring

[rmel]

Joeri brings up a point worth looking at. You can eyeball the Axle alignment, or measure
the 2'nd spring length. If the Axle is rotated one spring would be compressed while the other
extended. These springs are progressive so a compressed spring would have a higher KP value.

I am more suspicious your rig was fitted with the stronger springs. You would find 3 green paint
marks (now perhaps long gone) indicating the strongest spring, one mark for the weakest. To
put this in perspective, weakest spring value is 3590 Newtons, strongest is 3963 Newtons -- MEASURED
at 240MM, just under 10". I assume Steyr was thinking 240MM was under typical loading conditions,
not empty not maxed out.

If your Axles are true, then that leaves replacing the springs with weaker ones or cutting the ones
you have down, e.g. take a 1/2 turn off each end and see where that takes you. I have a spare set
of springs that were cut down as such -- long history with these springs. Last set of springs I got
from SAV were 2 green marks -- mid strength.

[MTPinz]

I may not have my nomenclature quite correct here...I was under the impression that a 716 was a diesel version of a 710 4x4 and maybe came with a heavier duty spring in the rear? I guess what I was getting at was that maybe someone swapped in a hd spring from another model or something.

Are the 710m and 710k springs the same? I don't see any different part numbers listed for different versions anywhere.

I'll check on the axle twist, but nothing seems out of the ordinary or too wonky, ha!