Rear end suspension sag

[Malcolm26 Junior Member Find all posts View Profile Close Malcolm26]

Wondering if any one has any suggestions on towing I have a light weight camper ( tare 750k ultimate camper ) on the latest model 150 Prado with a 2in lift.

the rear end still sags even after fitting a tow bar bracket to increase the height which is just under the rear door ( so the door still opens) not knowing much about air bags which I have heard can solve the problem to get the camper and car parallel any suggestions on type ,or where in Sydney thanks

[kizbot Member Find all posts View Profile Close kizbot]

What lift do you have? Are the shocks adjustable? If not, you could look at a heavier rated spring on the rear. Airbags are also an option but my personal opinion is another thing to go wrong but that's just me. Likely fine.

[Malcolm26 Junior Member Find all posts View Profile Close Malcolm26]

Hi I have a Dobinsons upgrade which was upgraded to the middle level spec as advised which was supposed to be good for 300 kg unfortunately they not adjustable .

[404pug Avid PP Poster! Find all posts View Profile Close 404pug]

Have had Polyairs on 3 cars. Never any problems. They give the advantage of near normal ride when set at 5 psi but when pumped up to 30 psi will hold the
bum of the car up well. Other brands can have higher pressures. I run Dobinsons 325 in the back k with polyairs. I also havea set of 327 which hold more weight well but the back sits too high when unloaded. Polyairs distributed by Heasemans at Sydenham.

[404pug Avid PP Poster! Find all posts View Profile Close 404pug]

I would also be seriously looking at how much weight you are putting into the front of the camper and back of the car. ie. Check your weight distribution overall. It sounds like you have Dobinsons 327 which should do the job.

[Malcolm26 Junior Member Find all posts View Profile Close Malcolm26]

Hi , thanks for the advise , the camper is unladen )before I asked ), the rear springs are c59-325 and the shocks ims59-50701 how would I find out if it’s a 327 thank you

[kizbot Member Find all posts View Profile Close kizbot]

If you have 325's on the rear they are not rated up to 300kg. You need the 327's.

https://www.dobinsonsprings.com/toyo...n%20Components

[404pug Avid PP Poster! Find all posts View Profile Close 404pug]

OK I have the 325s too and they will sag a bit but give a good ride unladen. The polyairs will fix it. They have a set with 30 psi max and I think a set with 60 psi max. Air Bag Man similarly has a higher presuure set. All will do the job. Give them a ring. Both in Sydney. My camper weighs about 1100-1200 kg fully laden for an outback trip with a tow ball weight of about 120-130 kg depending on whether I have the 3 jerry cans on the front full. The back of the car is always well loaded on outback trips. Even if I put the heavier 327 springs in there is still a littlle bit of sag. This is normal. What doesn't happen is that neither spring bottoms out when laden in outback conditions, indicating that they are doing their job. Perhaps ring Zordos suspension in Brisbane for a bit of advice . Highly regarded as a Prado suspension expert on this site. At 20psi and fully laden the back of my car sags about 25 mm with the 325 springs. If you were towing all the time the heavier springs may improve the situation but the harder the spring you select the harsher the ride will be when empty. Measure the sag before and after loading. If it appears too excessive to you go back to the seller and see if they will swap your springs out for the 327 at no charge because the present ones aren't up to it. The cost of the airbags will be similar to the cost of the heavier springs with the same labour costs. Good luck.

[kizbot Member Find all posts View Profile Close kizbot]

Just wanted to add, I have Dobinson's suspension fitted by Zordo. The 327's are stiffer and rated up to 300kg but I can tell you for a fact they are still very comfortable and not a harsh ride. Zordo will give you good advice. If it was me i'd try the 327 first but worth calling John Zordo and asking if the front spring would also need to be looked at if going this way. He also fits airbags so best you speak to him.

[Malcolm26 Junior Member Find all posts View Profile Close Malcolm26]

Thank you all for the advise I will start calling tomorrow, cheers

[404pug Avid PP Poster! Find all posts View Profile Close 404pug]

My only issue with the 327 spring is that my car is a 5 seat GX. These weigh over 100 kg less than the GXL and most of that difference is the rear air con and 3rd row of seats which are at the back of the car. The unladen ride is good and only marginally harder than the 325.....BUT being lighter in the rear it tends to sit too close to being over the legal 50mm. This may well not be an issue in the heavier versions. Incidently neither the 325 nor the 327 have shown any significant sag despite both doing 10s of thousands of outback and desert trips. Both are good springs but horses for courses.