parabolics or regular leafs?

[James86004]

I have TIC paras, 4-leaf on the rear and 2-leaf on the front. They've lasted 12 years and are still as good as new, though the front springs need an extra leaf to cope with the weight of the extras I fitted. Unfortunately, no-one seems to make 3-leaf front springs, so I'll be modifying my own.

I have wondered if the paras could be re-arched with a little more lift. If I could give my left front 1 inch more free arch, I would be golden.

 

[Snagger]

I rebuilt my 109 on a brand new chassis (Marsland). I have had problems with the steering pulling to the left ever since the rebuild, even though it drove straight up until the strip down. I hadn't done anything to the front axle during the rebuild, but I stripped and rebuilt it with new swivels, bushes and shafts just in case. The brakes had all been replaced, but I went through them with a fine tooth comb, just in case the left side was binding a little (no heat in drum, though).

I had a small accident early this year (back end of the 109 was damaged). I had the wheels all aligned by laser, and the shop found that the front left wheel is 1/2" behind the front right (the rear wheels are fine). Once aware of this, a quick look at the shackle angles on the front spring showed the right shackle to be near vertical (correct on 1-Ton), but the left to be inclined. The left front corner is also about 1/2" lower at the body line, or 1/4" at the chassis/spring line.

Swapping the springs over made no difference. Some quick measuring showed that the front spring bolt on the left side is 1/4" close to the chassis bush for the shackle on that left side. I suspect there is also a vertical discrepancy, not just longitudinal. This has put the axle on a 0.75 degree cant to the left, hence the pull.

You may have a similar problem if swapping your front springs from one side to the other doesn't have any effect.

I'll be putting it on a ramp to get accurate 3D measurements before welding up and re-drilling the spring hanger.

 

[Snagger]

I found that the two leaf fronts may have been a little light; when I got home to Canada and weighed the truck there was a lot of weight on the front axle. I heard a rumour that RM was working on a three leaf front set which may work better.

They're definitely too light for mine - spare wheel, pioneer tools, winch and steel rope, engine bay sound proofing (Noise Killer), Wright OFF Road interior matting, bullbar, roof rack, three fuel tanks, steering guard and jackable sills add a lot of weight.

I spoke to RM a couple of days ago. Jason (or was it Justin?) is going to be at the Peterborough show this weekend, so I'll catch up with him there. In a nutshell, though, they say there wasn't eneough demand for any of the manufacturers to offer three-leaf front springs, and that though RM originally did, they had to drop the line. They say to buy one front spring, cut the ends off (both leaves have identical camber and stiffness) and fit to the bottom of the existing springs. You just need the centre bolt for a rear spring.

That still leaves the problem of the clamps near each end; you'd have to remove the existing clamp, but how you'd attach a new clamp (rear spring type, so the top is bolted rather than folded) is a problem - most of us can't use big industrial rivets in a DIY application. Maybe drilling the new bottom leaf and tapping a thread to accept a bolt in place of a rivet would work?

I'm also not sure about the ends of the leaves - normally they either have a kink to have the ends meet but provide the space between leaves mid-span, or have nylon blocks.

I'll post the results of my meeting after the weekend.

 

[weatherm]

Well I did it. Way to much money later and the para's arrived at my house with all the goodies and then some.

I have done 3 ( 1 rear and both fronts) and on going to do the last one tomorrow. This whole process has more or less sucked. Not to in depth just monatanous and ohh well crap its time to cut WHAT.... sheesh. I had to go get new grade 8 bolts b/c I had to cut some prior unfortunately. I have spent about $80 bucks on parts and replacements that either I didn't have or needed to buy anyways (IE breaker bar) A sawzaw is nice for cutting bolts. Well most of the process is finished and after knocking out a lot of rust... eating dirt and risking getting crushed its almost finished. The ride is definitely higher.. roughly 1.5 in higher and does ride great ( at least around the block) I "should" be done by early afternoon tomorrow so pics will be up. One thing I HAVE TO SAY is my vehicle is level for once and is definitely nice and stout!


Required tools needed for suspension:
A buddy -- Beer IOU
Breaker Bar
Deep well sockets 1/2 drive
Angle grinder
New bolts
Air Gun
Blood
Sweat
Tears
& some 4 letter metaphors.


...pics to come

 

[TeriAnn]

I used to have 1-ton springs on our military chassis equipped Dormobile. It rode very very hard, even fully loaded with my family and camping gear. It cornered well, as long as the road was smooth, but a bump at the apex of the turn would be a little scary.

My Dormobile has had the same set of 1-ton springs with ultra high density plastic sheets (friction about same as teflon & holds up to repeated metal sliding) separating each leaf for 13 years now.

Last year Linus & I did a little highly subjective testing using his Dormobile with newish Hystee parabolics and my Dormobile. We concluded that the ride between the two trucks was similar enough that neither of us could tell the difference except that his truck leaned more on corners than mine did. I consider Hystee parabolics the best of the breed.

Just as an aside: Rover assumes that 75% of a vehicle's load will be carried by the rear springs. So the steps up in load capacity between spring options are much smaller for front springs than for rear springs. If you have a heavy winch & bonnet mounted spare, the rated off road capacity for standard front springs can easily be exceeded. Always load the truck as you do for a long off road trip then go down and weigh the front axle weight and the rear axle weight. If you have a big winch you may discover you need one ton front springs & regular rear springs. Over springing will get you the rough ride. That and increased leaf to leaf resistance. Under springing can get you a broken leaf.

Also: Rumor on the street is that Rocky Mountain parabolics are currently out of production. They went out when there was a price increase in steel along with the economy tanking and fewer people spending money for Land Rover parts.

Two things I've never trusted are friction to be there when I need it and the dynamic centre of gravity to stay inside my wheelbase when a vehicle sways on its suspension while driving a side sloping terrain.

 

[stevenmd]

...you may discover you need one ton front springs & regular rear springs...

TeriAnn - With a family of 7, my 109 would be loaded to the gills and I am looking for a small trailer to pull so I can keep stuff off the roof. Plus, I believe I will be fitting a 302 sometime next year (hope to have it done by Mendo). With the weight of my family (& any gear) and the 302, would you recommend one ton springs in both the front and back? She is being rebuilt for longer distance travel, not for trails where I need an overabundance of articulation - although, some articulation would be nice.

Would one ton springs all around be too rough of a ride when not fully loaded?

Should I consider one ton springs up front and 4 leaf paras in the rear?

Thanks!

 

[TeriAnn]

TeriAnn - With a family of 7, my 109 would be loaded to the gills and I am looking for a small trailer to pull so I can keep stuff off the roof. Plus, I believe I will be fitting a 302 sometime next year (hope to have it done by Mendo). With the weight of my family (& any gear) and the 302, would you recommend one ton springs in both the front and back? She is being rebuilt for longer distance travel, not for trails where I need an overabundance of articulation - although, some articulation would be nice.

A 302 will provide more power at idle than the 2-1/2 has a peak. The 302 is just a few pounds heavier than the 2-1/4 with cast iron heads and with aluminum heads is lighter than the LR engine. Email me directly if you want to discuss engine configuration & drive train.

My best advice on springs is to do your rebuild keeping the ruck on the old springs. Once you have everything finished load it up with all your gear, load your family and head off to your local public dump to get weights. At minimum you want front & rear axle weights. Then once you KNOW how much your truck weighs fully loaded for a trip pick the springs you want to use and do a spring swap.

It is too easy to guess wrong if you buy springs without knowing the vehicle weight. You may well find that with all the space your family takes you don't have space for much heavy gear and the lightest rear springs would work best. And no you do not want to mix leafs & parabolics.

What are you doing for a third row seats? Forward facing folding jump seats? A Jeep rear bench seat? or ?

 

[weatherm]

TerriAnn and everyone,
I have finally got the other rear one on.. what a BEAR! got everything set it drove it around a bit and let everything settle.. cranked down on everything one good time and this thing rides great. A difference between night and day for sure.

I am satisfied.. got mine from Rovers North. All in all $1130 was spent and that was some other tune up stuff involved also so.. 1130 was the total.

It sits up real high in the rear and the fronts are considerably higher.. looks stout

pics up soon

 

[stevenmd]

What are you doing for a third row seats? Forward facing folding jump seats? A Jeep rear bench seat? or ?

Still researching that at this point. I'd like to put all bucket type seats but she's kind of narrow. Might end up using old UPS seats.

Will be in touch shortly regarding engine configuration. Dan (aka tigerdan) is going to spearhead the conversion for me. He (as have I) has been enamored with your conversion for some time.

 

[Snagger]

Also: Rumor on the street is that Rocky Mountain parabolics are currently out of production. They went out when there was a price increase in steel along with the economy tanking and fewer people spending money for Land Rover parts.

I was told that the problem was the US steel supplier producing an ever deteriorating quality of steel. RM reached a point where the quality was no longer high enough and switched to a Japanese supplier. However, the new supplier bumped RM down the priority list a few times, causing the delays. RM had new stock over here last month, but much of that hasd gone again. Hopefully, their supply will become more reliable.

 

[weatherm]

Pics as promised.. did a full tune up and fixed a leak runs great!

 

[lstrvr]

I was told that the problem was the US steel supplier producing an ever deteriorating quality of steel. RM reached a point where the quality was no longer high enough and switched to a Japanese supplier. However, the new supplier bumped RM down the priority list a few times, causing the delays. RM had new stock over here last month, but much of that hasd gone again. Hopefully, their supply will become more reliable.

Thats the problem when we compare our experiences with Parabolics. A set of TIConsole or Heystee springs can very dramatically depending on their age, as the manufacture has changed factories and metal suppliers a number of times. I know of people that have owned TIC's for close to 10 years and absolutely love them, and then others of us buy the same item and it fails within a year. They may share the same manufacture name, but they don't necessarily share the same quality.