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Greg4427
28th April 2021, 02:15 PM
I’ve been reading the Perentie Owners Forum on Facebook and there has been a post in regard to how stable/unstable they are at the higher speeds in excess of 100 kph. I’ve driven them in the army but never in excess of Convoy speed of 80kph which I hold they are pretty ok at. However now that I have my own RFSV I’ve made a few changes as I’m thinking about it more as a daily driver.

I’ve changed out the split rims and Goodyear’s and now have HD Wolf 16” (16.5) and Toyo M/T 235/85/16R, wheels balanced and alignment and although I can get above 100kph I still regard it as a bit unstable. I have to remind myself that it’s “Fit for purpose” as a military spec off road vehicle and not a modern 4X4. So I’m happy to cruise along enjoying the serenity around 80-95kph unless I’m on arterial roads with someone behind me.

The suspension is fine, it’s also a higher vehicle with the 2” lift as standard with raises the Centre of Gravity contributing to some lean on curves etc and scary moments but again that’s not what it was spec’d to do. When it had its pre roadworthy undertaken it was very thorough and all issues addressed. In retrospect I’d probably go for a wider tyre to feel a bit more planted.

Anyone have thoughts on the subject?

powerband
28th April 2021, 03:33 PM
Hi, I have fitted 3 degree arms after I drove one with them. Night & day, more stable on the dirt & sweeping bends, dirt or tar.

Paul.

wpalmo
28th April 2021, 05:09 PM
What are 3 degree arms?
When you say it has improved the stability/ride, can you explain in what way.
Have you fitted them to a RFSV?
Regards Warrick.

cjc_td5
28th April 2021, 05:37 PM
What are 3 degree arms?
When you say it has improved the stability/ride, can you explain in what way.
Have you fitted them to a RFSV?
Regards Warrick.I presume the cranked arms go on the front to correct caster angle if lifted a lot.

If lifted a lot the front axle effectively rotates on the front radius arms, reducing caster angle. Reducing caster angle will reduce stability at speed.

Bazzle218
28th April 2021, 07:49 PM
Hi, my opinion: Let me say i drove them all from series 2 gun carriers to 6 x6 GMVs . The only stability issue was when we went from leaf to coils. Drivers used to panic with the coil roll / action when cornering and guess what roll. Defence fix was for all drivers to hop in a perenti and full left lock pedal to the metal in first and do some circle work to show they would not roll when cornering, and do the same on full right lock. I can say with my hand on my heart my old GMV full laden and probably overloaded would pull over 100 kph all day every day. Why fix what's not broken. Drive to the conditions and capability of the vehicle and there should be no issue. My opinion and definitely not a shot at original poster, Baz

100inch
30th April 2021, 11:33 AM
Check your panhard rod length (due to to lift), find a matching steering dampener for your tyre size. Ensure all A-frame bushes and ball joint are in good order. Personally I would also consider fitting sway bars. The small reduction of wheel travel will not stop you once 4wd-ing.m

pjh4159
4th May 2021, 07:17 PM
I’ve been reading the Perentie Owners Forum on Facebook and there has been a post in regard to how stable/unstable they are at the higher speeds in excess of 100 kph. I’ve driven them in the army but never in excess of Convoy speed of 80kph which I hold they are pretty ok at. However now that I have my own RFSV I’ve made a few changes as I’m thinking about it more as a daily driver.

I’ve changed out the split rims and Goodyear’s and now have HD Wolf 16” (16.5) and Toyo M/T 235/85/16R, wheels balanced and alignment and although I can get above 100kph I still regard it as a bit unstable. I have to remind myself that it’s “Fit for purpose” as a military spec off road vehicle and not a modern 4X4. So I’m happy to cruise along enjoying the serenity around 80-95kph unless I’m on arterial roads with someone behind me.

The suspension is fine, it’s also a higher vehicle with the 2” lift as standard with raises the Centre of Gravity contributing to some lean on curves etc and scary moments but again that’s not what it was spec’d to do. When it had its pre roadworthy undertaken it was very thorough and all issues addressed. In retrospect I’d probably go for a wider tyre to feel a bit more planted.

Anyone have thoughts on the subject?

I have a TD5 110 with Roverdrive installed and can easily get to 120kph but it is so important to run higher tyre pressures if doing these speeds as the tyres on 16inch rims can squirm from side to side if you change direction quickly making the vehicle unstable when running on lower tyre pressures.

tc_s1
5th May 2021, 01:39 PM
I have a TD5 110 with Roverdrive installed and can easily get to 120kph but it is so important to run higher tyre pressures if doing these speeds as the tyres on 16inch rims can squirm from side to side if you change direction quickly making the vehicle unstable when running on lower tyre pressures.I have few concerns about driving any of two Perenties or the county 110 and have routinely had them to +/- 120kph, however it's about that speed I've found I develop much greater concern with regard to stopping, and that normally keeps my driving sharp and well distanced from anything in front.

Greg4427
12th May 2021, 04:06 PM
Well 120kph is outta my naturally aspirated range that’s for sure. I’m happy to just puddle along at 105kph if pushed by traffic, otherwise I like to enjoy the scenery at lower speeds and let Barney enjoy himself. I replaced the empty steel jerrycans at the rear with full water ones thinking that may help its skittishness. I also have the dickie seat out and only one spare on the back instead of the usual two for an RFSV. The full jerrycans have helped I must say. Might also get a second HD Wolf with Toyo M/T as well to help keep the back planted.