Thread: Speedo correction D2 on 32's

Originally Posted by terraaustralis

.....

The main disadvantage ....

if it came to reliance on an inaccurate speedo, or a psudeo accurate GPS as your main speed indicator/odometer .. I'd have the inaccurate speedo any day of the week.

Don't get me wrong, I love all things mapping and GPS based .. bit of a GPS/mapping nut here, but not the way you're describing.

main disadvantage is when GPS reception is marginal to zero.
eg. smart devices are great coz their smart .. but not perfect.
I've had many smart devices, of many brands, and losing GPS lock in the city is not hard. It's not hard to produce a GPS track showing I've gone from one point in the city to another point as the crow flies about 5klms through hundreds of buildings in a second or two.

So that issue then questions the accuracy of the odometer that the GPS is keeping a track of.

GPSes don't work in tunnels, and lock can be temporarily lost in deep canyon/gorges quite easily.

An 'inaccurate' speedo is usually accurately inaccurate at least. that is, it'll be consistently inaccurate if there are not electronic issues and it's due to only tyre size.

My D1 came with 'inaccurately' size 255/70s where it's supposed to run on 235/70s.
Speedo is almost spot on(1k/h out at 100 k/h) but the odo is out by 8%(shows under).
So I know this and factor it in if I have to estimate the road sign distances compared to what my odo shows, if fuel supply may be marginal.

I've never found the D2 speedo needle 'hard to see' but if you refer to night time driving(maybe??) .. maybe a set of LED dash lights could be something to look into.
I did that for my D1, and brother wants them for his D2 now too.
Only problem I subsequently found was that they were too bright on dark lonely outback roads and reduced my outward periphery vision ... so I bought an instrument dimmer rheostat from the UK(we never got them in Au, only Japan, US and optional in the UK from my research), fitted, and now I'm happier than Larry ever will be.

ps. wiring is a lot easier than you think it is.

pps. for GPS testing(on Android) I've used GPS Test for many years now .. free and similarly large interface to what you described. But I only ever use it for checking sat status on devices when a mapping issue pops up(it's always lost satellite tracking).
For mapping nothing but OziExplorer. Had it for what feels like eons! And, so I've amassed more Mb's worth of mapping than most folks store on their entire computer HDDs!
I recently tried out an interesting OSM based mapping app called OsmAnd. Maps are stored locally, so when at lake Eyre, you have mapping no matter what. Not a fan of Google's mapping data, pretty much useless in the bush. OSM is usually more accurate(but real topo maps more accurate).

ppps. main reason for my reply here is that very soon we'll be tackling brother's D2, his 245/75's have knocked his speedo out by too much by his reckoning(6 k/h under or more). I'll reply back as to our success or failure with it.