Has anyone upgraded gen 4 tyres without going bigger?

My wife's Jimny came shod with Dunlop GrandTrek AT20s, which just happens to be a tyre that I've had on at least two other vehicles - a Nissan XTrail, and a Mitsubishi Pajero iO - neither of which was as "squirrely" on the AT20 as the Jimny was.

You could put the difference down to the fact that both of those vehicles were larger & quite different to the Jimny in terms of suspension & wheel base, but, if you're going to blame it on a tyre being "rubbish", then, maybe I should have had a "rubbish" experience there too - I didn't

Maybe this is just a coincidence, maybe not, but both of those vehicles just happen to take a 215 tyre as the stock width and that was the width of the AT20 that I was running on them.

Having had the AT20s on at least three vehicles, I would describe my experience with them as 'meh", neither good nor bad, on two of the three, the AT20s were replaced with GrandTrek AT3s in the same size, which were marginally better, on the third, the Jimny, the replacement was a General Grabber AT/x in a 215/70R15, significantly better, whether it's due to the wider footprint or the different tread pattern/compound, that can be debated.

Something else that I think factors in with the perception of handling and ride is tyre pressure. We all know that many times a jimny will come from the dealer with the tyre still at transport pressure instead of the recommended and tyre fitters are no better because everything else has low profile tyres at 35psi so that is a kind of default in their minds. However suzuki also take some of the blame here too as for the last 10 years they have set the tpms to 26psi arbitrarily for both axles. OK fair enough but prior to that the recommended pressure was 23psi front and between 23psi and 30psi rear depending on loading. This was correct based on the load index of the tyres and gave nice even wear and good handling and ride. It even to some extent masked the factory tyre being made of Teflon. However with a tpms vehicle having the same lowest pressure setting as used across the entire range instead of being specifically set for the jimny we are left in a situation where the recommended pressure is that same lowest threshold of the system and not the correct pressure for the load index of the tyre less a margin of safety before the warning. This situation only gets worse when you venture off road as there is no system override so unless you are prepared to put up with the dashboard screaming at you then you are stuck at 26psi often literally when 15psi might have seen you drive out.

I have a set of brand new Gen4 wheels with the 195/80 Dunlop Grandtreks on I've never fitted. I have had a set of BFG 215/75 all terrains on my car for 5 years. Both sets are on standard steel rims. I'll swap them over and see what difference it actually makes.

fordem wrote:

Having had the AT20s on at least three vehicles, I would describe my experience with them as 'meh", neither good nor bad

I agree, the Dunlops are both 1) superior to the Bridgestones that came standard on the early Gen4s, which rightly deserved their poor reputation, and 2) nothing really to write home about.  Not living in the Caribbean, I use the Dunlops only 6 months of the year, but they are in every sense adequate.  In winter, I am by necessity more careful about the type of rubber I put on the Jimny, since winter driving on the shores of the Baltic is a life and death matter.

To those who say the Jimny has go-kart like handling on different tyres, well, maybe we have driven different go-karts.     In my opinion, the J was never intended to handle well in absolute terms, and it doesn't.  Fortunately, I didn't buy the J for its handling.

About the tyre pressure issue, I completely agree with @Lambert that it is a key issue and that the way Suzuki set up the Jimny's TMPS is deplorable.  But remember, there is always an option to get a TPMS "spoofer" box to override the sensors-- relatively cheap item and very easy to set up.  The simplest version is just a small transmitter that drowns out the radio signals from the sensors mounted in the wheels, overriding them with signals showing whatever pressure you program.
 

They aren't absolutely rubbish ect, but by comparison they are on the jimny.
I ran them for most of a year, used them off road, on dirt roads ect and they did the job.
But they don't grip nearly so well in the narrow tread on a light vehicle, the more beefy rough terrain tires make it more stable, at least on the 5 door they are as good as putting 215's on.
But I do think they are the reason people seem to automatically put bigger tires on, but it's a bit of a catch 22 as they only put those tires on because they know the 1st thing most people will do when they get a jimny is replace them.

Two points ...

First - in the Caribbean we are perhaps blessed in that our governments don't legislate on the "lowest common denominator, intelligence-wise", ADAS is neither mandated nor supplied, nor is TPMS, so I'm free to set my pressures where ever I choose.

Second - I learned a long time ago not to trust dealers & tyre fitters to set the pressures correctly, my dealership sets the pressure to 35 psi, I can feel that the tires are over inflated, and that shows up in the feel of the steering, rather than the "skittish" rear end that was the issue with the OE Dunlops.

One last thing, you'll only get the go cart sensation in the three door, the five is a completely different animal - my wife has the three, I have the five.