Date: Tue, 10 Dec 2019 09:45:39 -0800
Reply-To: Dan N <dn92610@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dan N <dn92610@GMAIL.COM>
Subject: Re: Tire pressure recommendation... please
In-Reply-To: <DM6PR10MB40598861D73F57E49A5FBC76A05B0@DM6PR10MB4059.namprd10.prod.outlook.com>
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thank you Dennis,
I didn't choose that 215/65R16 tire/rim combo, it's inherited from the
previous owner. You're right about the sidewall translating into harsh ride.
- at 65 the side wall is not as tall as the 27x8.5R14 but the diameter are
the same on both.
- it's 8 ply versus 6 ply meaning harder side wall
- I notice the sidewall of the 27x8.5R14 bulges out more which means it's
more flexible
- and yes a tintop is lighter than a full camper westy..
I'd think the a 215/70R15 is better choice.. well ... learning from someone
else mistake
dan
On Mon, Dec 9, 2019 at 7:44 PM Dennis Haynes <d23haynes57@hotmail.com>
wrote:
> That tire I am familiar with. It is a beefy built to avoid damage of a
> tire if ever there was one! Besides the load ratings this is a very stiff
> tire and in my opinion just not right for the Vanagon. The Vanagon just
> doesn’t have enough weight and road isolation to make this work. Many folks
> jump off these after 2 or 3 seasons.
>
>
>
> For proper inflation you really need to get the load-inflation table for
> this tire. This type of tire requires the full rated inflation pressure (65
> psi) to reach full rated capacity of 1,930 pounds. The 103/101 load index
> shows the derating for dual tire applications. As roads are crowned duals
> have the capacity lowered due to the uneven loading.
>
> I don’t have the load/inflation chart for that size. We can extrapolate
> with the 215/70-15LT as that is similar diameter. As this heavy duty tire
> needs more air for a given load to reduce the heat buildup from flexing you
> will see that you probably still need 40-50 psi to carry the rated axle
> weight. Amazing how regardless of tire choice we often come back to this
> pressure range!
>
> Something to note, if you add the front and rear axle weights you will get
> a number higher than the total vehicle weight rating. That is not an error.
> Load both axles to the max and vehicle is overloaded. They know you can’t
> perfectly balance the load front/rear or side to side. That also takes
> partial care of that tire derating when they went to the XL rated instead
> of LT tires in 87. Now that I have scales I find it interesting that the
> passenger vans with 2 folks up front are front heavy.
>
>
>
> Dennis
>
>
>
>
>
> *From:* Dan N [mailto:dn92610@gmail.com]
> *Sent:* Sunday, December 8, 2019 4:31 PM
> *To:* Dennis Haynes <d23haynes57@hotmail.com>
> *Cc:* vanagon@GERRY.VANAGON.COM
> *Subject:* Re: Tire pressure recommendation... please
>
>
>
> thanks a lot Dennis for the explanation..
>
>
>
> the suspension was fully rebuilt about 500 miles ago, shocks are Bilstein
> HD, tire are 215/65 LT R16 BFG AT KO2 - 103/100S, load range D, 8 ply...
>
>
>
> dan
>
>
>
> On Sun, Dec 8, 2019 at 1:09 PM Dennis Haynes <d23haynes57@hotmail.com>
> wrote:
>
> Yes, as tires get larger less air pressure is required for a given load at
> a given speed. The BFG is also a hard riding tire due to the particularly
> stiff sidewall.
>
> I am not familiar with the BFG "Baja" tire. Is this an XL or standard
> tire? This can make a difference for inflation pressure.
> Syncros also ride harder than 2WD especially in front, the coil spring is
> shorter and depending on shocks and other choices things can be drastically
> different. Shocks and the upper control arm bushings can fail in ways to
> actually bind and stop normal movement which can also effect ride.
> Unfortunately only way to test and confirm is disconnect the upper arm from
> the ball joint to check the bushings and remove the shock-spring assembly
> to test the shock.
>
> Getting back to the tire, if this is a standard load rated tire, 98 load
> index, it actually reaches full load capacity of 1,653 pound at 36 psi.
> Between 36 and 51 psi there is no increase in capacity. This range is for
> rolling resistance and handling.
>
> If this is an extra load tire, 102 index that tire reached full capacity
> at 42 psi.
>
> From experience running the 215/65-16 38 to 42 front and 42 to 48 rear
> seems to work and feel right. If still too harsh look for suspension
> issues.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Dan N
> Sent: Sunday, December 8, 2019 3:12 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Tire pressure recommendation... please
>
> hi all,
>
> one of my van (tintop Syncro) has BFG Baja 215/65R16.. what's the correct
> tire pressure for Front and Rear?
>
> let me explain... on my other van (tintop) I have General Grabber ATX
> 20x8.5 LT R14, I put 42psi/Front and 46psi/Rear and it's fine - but if do
> the same on the Syncro with 16" tires the ride is quite hard...
>
> as for reference on my SUV they recommend 32psi Front and Rear on
> 275/55R17...
>
> i am lost... it seems to me the larger/wider the tire the lower pressure
> is required...
>
> thanks for any help
>
> dan
>
>
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