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View Full Version : I Need To Get it Out Of My System!


Bikeman
01-08-2008, 07:02 PM
Wanting more lift and tire, I would like to drive a stock-geared 80 with 35's, normally aspirated, to see if the powereloss/powerband is tolerable before I eventually get gears. I have read all of Nay's posts on the subject and have re-geared 3 different rigs before, so I know the importance of changing gears. Right now I'm on 32.5" tires and most 315's are 33.5" to 34", so I know the difference. Can anyone help me out by me driving their rig briefly? I also know the ramifications of going over 3.5" lift and the cost associated with it. BTW, I have Mark's speedo box and borrowed GPS for install this week.

Romer
01-08-2008, 07:43 PM
315's are best with 4.88's in my opinion. Nay went quite a while saying you don't need to re-gear and then went the other extreme to 5.29's.

My truck has been re-geared and is supercharged so it won't help you. There are a few normally aspirated trucks that have been re-geared to 4.88's running 35's. It might be better to drive one with the gear change and 35's to see how it drives.

The gear change is really a must IMOP if you are going to drive in the mountains at all. It's also great for offroad drivability. The lower gears really help.

Tch2fly
01-08-2008, 08:33 PM
Mike,

I ordered my 315s today and they should be here friday or early next week. It would be pretty easy to come down to my place and bolt them on your truck for a test drive.

Bikeman
01-09-2008, 06:57 PM
Wow Mike, if the weather is good, I might take you up on that!

Beater
01-10-2008, 07:03 AM
it's all relative, and mainly a seat of the pants thing. I wheeled for years with 35's and 3.54's in a different truck with similar power curve to a cruiser. no big deal. a 3.75:1 xfer made up for it in low range.

I can say after 3 years of an 80 on 35's and 4.11's, that unless I had money to spare/burn, I wouldn't do it. I found that running the truck in ect mode, around town, and with the o/d off in the hills satisfactory. But, I resigned myself to the fact that I was driving a 6200 plus pound truck with a torquey motor, not a hp motor.

Red_Chili
01-10-2008, 08:22 AM
If Ige can wheel Old Chinamans Gulch in the snow in high range... :lmao:

Tch2fly
01-11-2008, 07:07 AM
Didn't you say you have 255/85-16s??

Why do you need to drive someone elses truck ....the latest 4wd Toyota Owner mag (pg 66) says those ARE 35s :lmao:

Bikeman
01-11-2008, 02:24 PM
Didn't you say you have 255/85-16s??

Why do you need to drive someone elses truck ....the latest 4wd Toyota Owner mag (pg 66) says those ARE 35s :lmao:

Doesn't look like a typo since the article talks about 35" tires being the maximum for a toy IFS rig. :confused:.

I just went outside and measured my spare, which is a BFG MT in 255/85/16: 32.5" unloaded!

Uncle Ben
01-11-2008, 02:31 PM
Doesn't look like a typo since the article talks about 35" tires being the maximum for a toy IFS rig. :confused:.

I just went outside and measured my spare, which is a BFG MT in 255/85/16: 32.5" unloaded!


P metric converter (http://www.4lo.com/calc/gearmetric.htm) = 33.1

Tch2fly
01-11-2008, 02:55 PM
Doesn't look like a typo since the article talks about 35" tires being the maximum for a toy IFS rig. :confused:.

I just went outside and measured my spare, which is a BFG MT in 255/85/16: 32.5" unloaded!


Ben Crockett (the author) and I have been having an email conversation about the article. He sent me to the BFG site to look up the specs and they even say 33.3" :hill:
I haven't heard back again .... I'll let you know what happens ;)

Bikeman
01-11-2008, 07:57 PM
I look forward to reading that mag cover to cover. You've got a good eye, Mike now that I know I have 35's:D

powderpig
01-12-2008, 06:46 AM
Most tire companies mount to the proper reccommended width rim, then inflate to max tire inflation before taking the static tire measurement(unloaded static tire size). Mount this on a truck you then have loaded static tire size. Next you drop the tire pressure to a more cilivized dynamic road pressure(like 32-36) and you have less height. So a tire will never measure what the manifacture says mounted on the truck. Most tires are various sizes even rated at X size. The worst was I was looking at Yokohama I/T for the curiser for Robin to feel safe when driving in the hills. The Web site stated the 315/75/16 at close to 33.9. The big O tire web site stated the 315 I have to be a 34.5 The General tire I did get was a 34.8 tire and looks big over the Big O tire. And the loaded height of the big O at 36 psi is close 33.5.
Alot of overlanders like the 255/85 aspect tire for less road resistance and better fuel ecomany, while still getting the same height they want. later Robbie

powderpig
01-12-2008, 06:54 AM
Thinking back on some stuff. Tim N got some 295/75/16 (closee to a 34) before he regeared and went to 35s. If you do not want to regear this may be a good choice as you will more than likely only loose maybe a 1/4-1/2 inch under the alxe depenidng on the tire company. You may even have equal height under the axle. Less weight of tire and rim combo, less width for rolling resistance. Just one more thought for you. I did run 315 MTR's for a few weeks before regearing my truck and I hated it. Truck did not pull the hills as well, had to run into the higher RPM for longer than I wanted. Fuel ecomany suffered as well. On trial perfromance was not great. For me it made sense to regear if I wanted to go with 35 or bigger. I could not have been happier after I regeared. Good luck on your choice. Robbie

Nay
01-12-2008, 04:26 PM
It's livable. I thought it wasn't a bit worse than being on 33's...bogged down bad on the same hills, had to drive with PWR on and OD off on the same hills, and OD off is really better matched at interstate speed to 35's.

Now having said that, I don't think 33's are very livable at our elevations for any period of time either. Yes, I went 5.29's because if I was going to spend I wanted the extra gearing, but I'd plan for a regear within 1-2 years.

The biggest issue you'll have, IMO, is if you want to do more serious crawling at higher elevations you're just going to need a bit more throttle. It really comes down to driver fatigue. It just gets old having the pedal to the floor so much, but offroad the auto transmission compensates for a lot and the hand throttle if you have it adds a lot more control.

So...if you really want the 35's and will regear at some reasonable point in the future, you don't need to buy 33's in the interim. If it helps, my experience is on a true 35" tire (35x12.5x16 trxus MT).

But I'd drive one so you know. You'll still have more power than a poor 3FE :D

Bikeman
01-12-2008, 04:48 PM
Good feedback, thanks. Right now the truck is set up for overlanding (sans roofrack and RRT for winter garage parking). I plan on more moderate trails this year with the wife and the 2 y.o. who can finally go. With the weight I will have on it, coupled with high-elevation and above-timberline trails, the rig will be ruined with 35's and no regear. With holiday business that was below avg., I need to watch my pennies anyway and make sure I can pay myself until spring when the bike season starts! I'll just keep reading Overland Journal instead of drooling over 80's with 35's and more lift. I have the near-perfect suspension setup at 3-3.5" lift anyways (perfect would be FOR according to Nay:D). Better flex and more wheel travel than a bump-stopped higher C-G rig. And I am not going to spend $1400 on caster correction (arms and driveshaft:rolleyes:). I need $$ to by my stove and fridge anyway:blah:.

Nay
01-12-2008, 09:14 PM
Right on :D

It is easy to forget that 33" is a lot of tire - you can do 95% of what CO/UT have to offer on 33's without too much sweat.

I remember when I had to get out of my XJ due to my little girl being on the way (#4 :eek:), and being up in Vail and seeing an 80 on an OME medium lift and 295 BFG AT's. All I could think at the time was "this is exactly what I've needed for years". In context, those years were spent optimizing an XJ. You can spend a lot of money trying to solve that 5% most of us don't really need to solve.

Now I've moved a bit beyond that, but outside of web wheeling it's all at the margin stuff. Yea, I like FOR and pushing conventional wisdom in general, but I helped design FOR so of course it like it :hill:, and the 80 handles 35's so easily how do you refuse? Especially coming out of a Jeep world where you struggled at times to fit 31's :D

Nothing worse than spending money because of drool pics on the net :rolleyes:

Of course, you could put L shocks on your lift and run 35's no problem :D

Tch2fly
01-12-2008, 09:54 PM
Of course, you could put L shocks on your lift and run 35's no problem :D

I am reasonably well versed in suspension theory, although I rarely share my ideas in forums (for a variety of reason) I can appreciate those who do. Since this is at least the second time I've seen you make this statement I'm just curious enough to ask you to explain it.

Bikeman
01-12-2008, 10:07 PM
If I can butt in, do you mean that since most have to drop bump stops for 35's not to rub badly on a shorter lift (I will never do that), you have to with L shocks anyways, so they don't become their own bump stops and get destroyed? Man where are those Billie 5100 short body shocks with pin ends when you need them?

Tch2fly
01-14-2008, 01:02 PM
The last response from Ben (Crockett)
....here is the reason I sided with the 35" measurement and not a 33". Given the average standing height of tires vs measurement, BFG's site measurements more closely side with what most brands are calling a 35. Mounted on our narrow rims as reviewed at suggested pressure, we found the tires to measure just a hair under 34", putting it well over the average of what most brands consider a 35......

Must be that "new math" I heard tell of ...I guess I'm going to say my new 315s are really 36s :woot:

Uncle Ben
01-14-2008, 02:13 PM
The last response from Ben (Crockett)


Must be that "new math" I heard tell of ...I guess I'm going to say my new 315s are really 36s :woot:

Crockett's starting to sound like he is running for a political office! ;) :lmao::hill:

wesintl
01-14-2008, 02:16 PM
It's really easy to deduce with some common logic. Since a 35x12.5 bfg tire only measures 33" then a metric tire of the equivalent 33 is now a 35. Genius.
:rolleyes:

Bikeman
01-14-2008, 02:35 PM
:lmao:

corsair23
01-14-2008, 05:35 PM
AWESOME!!

I've gots 35s too....Yiiiiiipppppppeeeeeeee :D

Guess I better get The Whale regeared then :)

Bikeman
04-27-2008, 08:44 PM
Well, an update: I just installed Dunlop Radial Mud Rovers in 315/75R16 on a spare set of factory alloys. The tires are acually Treadwright retreads using Dunlop casings. They stand 33.75" loaded. Not much of a power loss over the 255/85's. At $95 a crack, with a 25K warranty, I thought I'd try them. They were shipped to me for $450 to my business. I even mounted them myself on my buddie's tire machine. I have Dynabeads on order to balance them, but they are pretty smooth without any balance.

With 3.5" of lift, they fill in the fenderwells very nicely, like the 80 was made for 35's.

Hulk
04-28-2008, 08:19 AM
That's a deal on tires! Wow.