Bought a V70 T5 with Suspension and Springs, WAY TOO STIFF

[babelfish]

Trust me, try 32-30
Two lbs makes a hell of a difference on these cars and again, trust me, it's quite safe (for the car and the tire) unless you have over 400+ lbs in the back, are consistently driving at high speeds in 90 degree heat, for miles on end.

The T5 below is low and stiff, w/ sway bars, chassis brace, H&R springs and Konis, running 31-29 lbs and the ride is very liveable.
I'm 66 with a bad back, trust me, if this one didn't work out I would put the stock springs back in but it's OK (and fun)

It handles quite well and I'm sure my cornering speeds would be even better if I jacked the pressures up 4-6 lbs all around, but the ride trade off is just not worth it on our rough roads here. (I've done it, it's a buckboard)!

A bit off-topic, but what wheels are those?

[98V70T5]

OK going to try 32 30 today!

Ok here is my full opinion.

The car feels so sluggish and draggy with this pressure. It soaks up bumps a lot better, probably almost as good as I would want at in town speeds (40-45). HOWEVER, the rolling resistance just sucks all the coast and effortless cruising that I've been accustomed to with the 2 other Volvo recommended PSI settings. I even looked at the MPG on the highway and its down to 21mph on a 60mph cruise compared to 24 on the higher settings. I could cruise 80mph without much effort, now it feels like I am using way more throttle to cruise on level highway. The same natural spot where the car likes to cruise is now only around 60-65, where as before, it was 70-75 even 80. By natural cruise I mean the point where you are just cracking the throttle to hold a steady speed. It almost feels like a dragging brake caliper or a boat anchor

Cornering went down slightly, and I can get all 4 tires to howl if I do it right , but this isnt a canyon carver. The rolling resistance really makes this car feel heavy, and I think I'm going back to the higher settings. Too bad there isnt a way to describe it any better, but it really feels like I'm driving around on 4 heavily underinflated tires.

[JRL]

Better tires
IPD sway bars
or
slow down
Try going up ONE pound at a time

[98V70T5]

Well I dont want to debate the slowing down thing Highway traffic moves fast here, 65 is about norm for the slow lane, 75-80 in the left lane, and usually you are behind, or part of, a big train of cars. Typical cruise is at a minimum 70 on the PA Turnpike, I-78 into NJ and NY really hustles. My point is I need to consider that I need to keep up with traffic.

Anyway, does your car feel heavy or draggy with those good tires at lower pressures?

One thing you were spot on about is the 2psi makes a big difference! I dropped it down from 34 in the front to 32, and notice the change instantly. A good PSI gauge is needed (have one!). Will try the one pound at a time. Thanks

[zhenya]

I run very high performance tires on my T5, (Michelin Pilot Exalto PE2) generally at 34/32 or 32/30, and can't say I notice any 'drag'. I get up to about 26.5 mpg with mostly highway driving, and have seen 28-29 mpg tanks on 100% highway drives.

[jblackburn]

Must be the set of tires. Mine's perfectly happy at 75 mph running 33/31. I have BF Goodrich on the front (they're about dead) and Yokohama's on the back. I'll be getting another set of Yokohama's I loved them so much.

My car has a "sport handling pack"; anything more than that pressure will jar your spine and I think it became too squirrly with the handling. Volvos ARE a heavy car, and drive like one. It takes some getting used to.

Dad has the MXV4's on his Accord - no idea what pressure, and I just don't like the way it handles - granted, it's a bigger car with a light nose, but the tires howl way too easily and the car feels like it wants to faceplant the nose into a corner. The electric steering that doesn't give feedback is pretty annoying too - I much prefer the lightened steering on the Jeep Liberty that's still connected directly to a rack and pinion. And the Accord is just awful in snow (this was with Bridgestones on it).

You've got to learn pedal control too - unlike the Honda, you've got to will yourself to get better MPG with these. Every time you stab the pedal, it will drink gas like a monster. I could drive my 88 Accord like a bat out of hell and still get 35+ mpg.

On average, I get about 24 mpg mixed city/country road driving. On highway trips, I usually get ~ 28-29 or above.

[Red-Arrow]

front 36-41 rear is the recommendation for 5 adults without the 2 children in the jump seat. 5 adults weighting 175 Ibs each is 875 Ibs, two kids at 80Ibs is another 160Ibs making a total of 1035Ibs now that is a a great deal of weight.

850 Wagon curb weight is 3387Ibs. Take 3387 and add the weight of 5 adults. 3387+875(5 adults)= 4262ibs.

Now divide 4262/36Psi(front tires)=118.38 This is the ratio we use to calculate the Psi to weight ratio in the front.

Add 3387+350(2 Adults)=3737total weight. Then divide 3737/118.38=31.56Psi for the front tires this sounds about right.

For rears 3387+525(3 Adults)=3912. Now divided by 3912/41=95.41 is the ratio for the rear tires.

Now take 3387and remove the 3 adults from the rear but we retain the adults in the front. so we cannot use the 95.41 ratio as we should split the difference between the two ratios so 118.38 - 95.41= 22.97 half this 11.489 then add this to the 95.41 to give 106.899 as a ratio for the rear tires. 3737/106.899= 34.95Psi


Now while farting around with these numbers I forgot Volvo had already given the total weight of 890ibs. 890/5= 178ibs per adult which sound average for a Swed perhaps?

To me it sounds like Volvo are correct and there is no error in their calculations and it also sounds like everybody who is recommending the lower Psi is correct. Now these numbers do not account for the stiffness of your tire sidewalls or the quality of the tires construction so these are only general guides and nothing replaces experience and the ability to judge a tires performance under variable inflations pressures.

Erm here I go to check my Psi.

[98V70T5]

Ok I have to give my impressions after a few days.

I think I really really like the settings JRL recommended I drove the car more yesterday, and it really drives nice. The dragging is just something I had to get used to. I was able to run it 75 on the highway for about 45 mins, and it hustles nice, rides GREAT! I think short of a long (400mi all highway) trip, I will be keeping it at 32F 30R.

What really got me a hot and bothered when I started this thread was I thought it was the shocks, and in reality its the tire pressure. I was only following Volvos advice for fuel economy I am still not sure of what shocks I have, it is a firm ride, but compared to last week its like a different car. Cornering is still very good (tested it on some long cloverleaf highway exits), and in town driving is pleasurable. As long as I don't get funny tire wear, I'm keeping it this way. I am up for tires in about 10,000 miles, and will be getting some really killer tires. No holds barred.

The only thing I'm worried about now, only because I read it on this forum, is premature wear on the steering rack. I have a brand new rack, installed last Oct, and don't want to ruin it. One thread on this site stressed to keep the tires inflated to Volvo specs to keep from ruining it. Myth?

Once again thanks, I have my car back!

OT: Best part of last night was seeing a 350Z convertible blow by me at least at 95-100mph. I was only doing 65. He took the same exit as me, which has a red light. As we turned left onto the main 2 lane road I got next to him, he wanted to run, and at 30 I just floored it. Car downshifted into 1st, and I was OFF! He got on it, but I put 2 quick car lengths on him, and by 80 I flashed my rear fog light because he wasn't gaining and I was pulling! Won by about 4 cars, and still pulling. HAHAH nice. I had the windows up AC on and was nice and comfy in my Swedish tank!

[JRL]

Steering rack?
Why would/should tire pressures effect the steering rack
Hint; they don't

[98V70T5]

I tried searching for the link, but gave up. It was saying something to the effect, the lower the tire pressure the harder the rack/pump has to work, and its more prone to blowing out. I figured it was a "Volvo" problem, because on other cars, like my Toyotas, I ran tire pressure in the high 20s low 30s, and never had a rack problem. You just have to take my word for it, I did read that here.