By Russ on Monday, May 07, 2001 - 02:51 pm: Edit

Those that have changed gears because of tires or whatever. What did you go with, what size tire are you running with those gears, and are you glad you did it? I may be looking into this in about a year, but I'm getting a head start now with info.

By ho on Monday, May 07, 2001 - 04:25 pm: Edit

235/85-16
with
4.10 gears.
yes i am very glad i did it.

By Keith Armstrong on Monday, May 07, 2001 - 04:28 pm: Edit

same as Ho...well almost. 7.50x16's w/ 4.10's
from GBR

keith

By david b. on Monday, May 07, 2001 - 05:17 pm: Edit

will 245/75-16 on stock alloys need new gearing on a 1995 Disco 5-speed?

By Bill Gill (Bluegill) on Monday, May 07, 2001 - 05:37 pm: Edit

I barely notice a power/acceleration difference on my automatic 96 with 245/75's - I'm going to play with the transmission kickdown adjustment cable rather than go for new gears. I also checked the speedo against my GPS this weekend, and everyone is right - my speedo is now dead-on - must have been reading high before.

By gil on Monday, May 07, 2001 - 05:43 pm: Edit

Ive got 265/75s on my 97 Disco 5-speed. No gear change needed and I blow the doors off stock automatics (as well as Monteros, Explorers, ML320's etc.) The speedo is a hair (1-2 mph) off but its no big deal and not worth correcting. I think the gearing in the 5-speed is perfect for the 265/75, so your 245/75 should be a non issue. Id go with the 265, trim the fenders a bit, which is very simple and almost unnoticable without it being pointed out that you did it. The steering radius is off a hair as well, but thats nothing that wheel spacers wont fix.

By Russ on Monday, May 07, 2001 - 06:03 pm: Edit

Thanks everyone! I just went with 265/75's and the stock gears are fine for around town, and the fwy but I want more for heavy loads, and towing. I figured 4.11's would be about right especially in the mountains.

By david b. on Monday, May 07, 2001 - 08:17 pm: Edit

Gil, do you run 265/75-16 on stock alloys with a 2" or 3" lift? I have a Rovertym 2". Will the truck be able to flex like crazy still, or will the tires prohibit it? How about your hill-climbing ability, do you still have power to go up hills and stuff?

By gil on Monday, May 07, 2001 - 08:25 pm: Edit

I run 265/75 on stock deep dish alloys for the street(just got NATOs for the trail) with OME HD. I have a 2" drop kit out back with sway bar off. I had the sway bar off the front to, but for civility I put it back on. Heres how it looks.
/image{artic}
/image{artic2}

By gil on Monday, May 07, 2001 - 08:25 pm: Edit

By gil on Monday, May 07, 2001 - 08:29 pm: Edit

as you can see, with minor trimming that big 'ol 265 stuffs right in there, no loss of power, couldnt be happier. I run 265/75 Pirelli Scorpion A/Ts on the road and Swamper Radials off the road. Its an awesome set-up, hope that helps.

By willis on Tuesday, May 08, 2001 - 11:11 am: Edit

do you ever use the Scorpions off-road? I was looking at them as a BFG AT alternative. I think they are cheaper.

By nadim on Tuesday, May 08, 2001 - 01:02 pm: Edit

4.7s, with 235/85 trac edges for the road (soon to be 265/75 BFG AT, ot Pirelli AT), and 265/80 16 TSL radials, soon to be (hopefully) 33x12.5x15s)...

the 4.7s are much cheaper in Lebanon that the 4.1s, so that was the main reason, but also, there are a lot of mountains and such, and little speed needed, plus when camping, i usually have to tow a trailer full of stuff!

hope this helps...

By Ron on Tuesday, May 08, 2001 - 01:08 pm: Edit

Nadim,

Are you using series style 4.7 gears?

Ron

By Discosaurus on Tuesday, May 08, 2001 - 01:09 pm: Edit

I still have original gears in my '96 5 speed
with 235/85-16's. It's fine...slow, but fine.

keith
discosaurus

By Tom on Tuesday, May 08, 2001 - 01:21 pm: Edit

Nadim!!! You may be my hero as I was hoping to find someone who had tried the 4.7's on a disco.

I am contemplating 4.7 gears with my 265/75 on road and 32x9.5 off road combo. What do you think of the 4.7's? What is your RPM's at 70 mph or so?

I would love to do the 4.7's so I have room to grow, but am araid that it will be too much.

Thanks,

Tom

By Bobby Disco on Tuesday, May 08, 2001 - 01:25 pm: Edit

Is everyone talking about the Differential gears??
Or somthing inside the transmission...I have a 5 speed with 235/85's and stock gears right now.

By Ron on Tuesday, May 08, 2001 - 01:26 pm: Edit

Tom,
There are actually two different types of 4.7 gears. The LR series gears and the ones that GBR sells, 4.75s actually I think. Maybe ashcroft makes them too. Anyway, the series 4.7s seem to be a quick, cheap fix. I can get them free I am sure and if they are from the front dif they almost always have nearly no wear (no full time 4wd on series trucks) but I have heard people strip them so I want to know if anyone has had success and not toasted them.

Ron

As far as RPMs just do the math

By gil on Tuesday, May 08, 2001 - 01:27 pm: Edit

Willis, I have had the Scorpions in the dirt, they work for light trail use, but for anything hairy, I wouldnt suggest them. They turn into slicks in the mud, but they are great on-road and significantly cheaper than BFG A/Ts.

By gil on Tuesday, May 08, 2001 - 01:31 pm: Edit

Ron, I know this isnt the point of changing gears, but what would 4.75s do to your highway cruising range? Also wouldnt they turn the fuel mileage in to gallons per mile as opposed to miles per gallon?

By Tom on Tuesday, May 08, 2001 - 01:37 pm: Edit

Ron,

I'll do the math, you got the formula?

Tom

By Tom on Tuesday, May 08, 2001 - 01:42 pm: Edit

Ron,

Do you have the formula handy?

Thanks,

Tom

By Tom on Tuesday, May 08, 2001 - 01:43 pm: Edit

sorry for double posting...my browser went goofy and i thought my first one was gone

By Ron on Tuesday, May 08, 2001 - 01:57 pm: Edit

Tom,

http://addie.home.mindspring.com/tech/gears.htm

Try that but just setting up a ratio will tell you that if you are at 3000rpm 3.54 you will be at 3991 rpm with 4.7 or 4025 rpm at 4.75. Of course tire size can be accomidated in the calculator I provided for you. You can even do it with tanny ratios.

cheers
Ron

By nadim on Tuesday, May 08, 2001 - 03:34 pm: Edit

Ron,

Yes I think I am...my mechanic in Lebanon also has a huge amount of spare parts, so I am not sure where the 4.7s came out of?...

But they work great to say the least, and they have stepped up the performance of the Disco a lot!

Hope this helps

By Rob Davison (Pokerob) on Tuesday, May 08, 2001 - 03:37 pm: Edit

4.75's is stupid unless you have 34" tires... wtf do you want so much time off the line? you realize you're highway cruiseing speed will be in the 4-5k rpm range.

and they are weaker... go read the www.greatbasinrovers.com web page.

i have 3.54 gears and 235/85-16 tires 1997 automatic. it is slow but reliable... i will someday install 4.10's when i get around to it, this will make it shift less and easier to drive. until then i'll just pop it down into 3rd and go a little slower, when the hills come.

rob

By nadim on Tuesday, May 08, 2001 - 03:41 pm: Edit

ok...Tom, and Ron...

The 4.7s are for sure from series trucks, as I remember the mechanic pointing to 2 109 SIIIs, and telling me that they were from there...

Well, as for the highway use, at least with 32" tires, I can now use the 5th gear, as with 3.54s there was not enough power to get into 5th...BUT, I think a 6th gear would help now...hehehe...

Tom, I never go over 62mph, therefore I cannot really tell you for 70mph...but 5th gear at 62, and I can still floor it and have the ooomph to accelerate...great feeling I tell you...

For trail use, the 4.7s are excellent. If you calculate the final gearing, the 10 forward gears give you enough choice that you need for every type of terrain...and when my tires go taller, then it would still work, getting the Disco closer to stock...