Part I can be found here for interested readers 
:
https://forum.ih8mud.com/80-series-tech/278215-37-trxus-mt-mounted-f-o-r-gen-ii.html
We took a non CM09 trip to Moab last week - I couldn't do CM due to work, but try to get out to Moab this time of year. Mostly family stuff in Canyonlands and Arches and a little bit of wheeling.
Anyway, in moving to 37's, my key concerns had been loss of streetability including difficultly balancing and road noise. I hated the Toyos for noise and never thought they tracked well, so curing that by going to 37's made perfect sense.
First, the 37" trxus are whisper quiet at 75 mph. They balance every bit as good as the 33's did, and deliver an outstanding ride. Combined with F.O.R. Gen II, this setup just plain cushy.
drove the first four hours back out of Moab, and in her direct words "The Cruiser is driving like a dream at high speeds, it's like driving the minivan".
She also did some wheeling out to the Colorado River Overlook in Needles, and said she wants her own 80 on 37's to really learn how to wheel it. So between that and the practically effortless 8 hour drive I did on the way out, the 37's have satisfied the upgrade criteria: quiet and immensely driveable on and offroad. I would drive cross country without hesitation on a family trip with this setup.
The 5.29's are spinning 37's perfectly, about 2,600 RPM at 70 mph, 2,850 at 75 mph. I have not noticed any loss of power going to 37's, and would say the narrower 37" Trxus are spinning more easily than the wide 35" Toyos they replaced. I honestly haven't notice any braking difference at all, but these tires are only 3 lbs heavier than the 35's I have been running for years.
So now to the important question: Do they really fit? Yes. And No.
I trimmed some rear fender before we left just to ensure extra room. So they stuff no issue, I could probably fit 38's if I wanted to as long as they were narrow enough (see first pic). I do have 3/8" longer LCA's to fix pinion angle, so I have extra room to the front of the wheel well.
But on stock wheel backspacing, they do rub the inner wheel with about 1" of up travel remaining to 2" bumpstops and heavily with about 1/2" remaining. Second pic shows the flex at 1/2" of up travel remaining. No way I could leave this alone with the wheeling I do.
I am installing 1" spacers to set the rims out - it is going to be close at my lift height to clear the inner wheel well lip, although at full stuff the tires are tucked way in so I doubt I will need any trimming. I'll post up those results as Part III
I did bottom the rear suspension at speed and just barely kissed the tire to the wheel well (as evidenced by a trace of green on the tire) I need to extend my bumpstops 1/2" to protect the shock anyway as I have 5" of up travel to the bumpstop and 5" of shock travel, so the shock is not properly protected at speed. This will mean no issue of compressing the tire into the body at speed.
I am confident that without any material extra trimming I will be running 37's clean on the F.O.R. Gen II kit. Stay tuned.
:https://forum.ih8mud.com/80-series-tech/278215-37-trxus-mt-mounted-f-o-r-gen-ii.html
We took a non CM09 trip to Moab last week - I couldn't do CM due to work, but try to get out to Moab this time of year. Mostly family stuff in Canyonlands and Arches and a little bit of wheeling.
Anyway, in moving to 37's, my key concerns had been loss of streetability including difficultly balancing and road noise. I hated the Toyos for noise and never thought they tracked well, so curing that by going to 37's made perfect sense.
First, the 37" trxus are whisper quiet at 75 mph. They balance every bit as good as the 33's did, and deliver an outstanding ride. Combined with F.O.R. Gen II, this setup just plain cushy.
drove the first four hours back out of Moab, and in her direct words "The Cruiser is driving like a dream at high speeds, it's like driving the minivan".She also did some wheeling out to the Colorado River Overlook in Needles, and said she wants her own 80 on 37's to really learn how to wheel it. So between that and the practically effortless 8 hour drive I did on the way out, the 37's have satisfied the upgrade criteria: quiet and immensely driveable on and offroad. I would drive cross country without hesitation on a family trip with this setup.
The 5.29's are spinning 37's perfectly, about 2,600 RPM at 70 mph, 2,850 at 75 mph. I have not noticed any loss of power going to 37's, and would say the narrower 37" Trxus are spinning more easily than the wide 35" Toyos they replaced. I honestly haven't notice any braking difference at all, but these tires are only 3 lbs heavier than the 35's I have been running for years.
So now to the important question: Do they really fit? Yes. And No.
I trimmed some rear fender before we left just to ensure extra room. So they stuff no issue, I could probably fit 38's if I wanted to as long as they were narrow enough
(see first pic). I do have 3/8" longer LCA's to fix pinion angle, so I have extra room to the front of the wheel well.But on stock wheel backspacing, they do rub the inner wheel with about 1" of up travel remaining to 2" bumpstops and heavily with about 1/2" remaining. Second pic shows the flex at 1/2" of up travel remaining. No way I could leave this alone with the wheeling I do.
I am installing 1" spacers to set the rims out - it is going to be close at my lift height to clear the inner wheel well lip, although at full stuff the tires are tucked way in so I doubt I will need any trimming. I'll post up those results as Part III
I did bottom the rear suspension at speed and just barely kissed the tire to the wheel well (as evidenced by a trace of green on the tire
) I need to extend my bumpstops 1/2" to protect the shock anyway as I have 5" of up travel to the bumpstop and 5" of shock travel, so the shock is not properly protected at speed. This will mean no issue of compressing the tire into the body at speed.I am confident that without any material extra trimming I will be running 37's clean on the F.O.R. Gen II kit. Stay tuned.
