Gears to go with
- Thread starter B-RONC70
- Start date
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You are gonna need a lot more than 4:11 or 4:56 to go with that big of a meat. I would say somewhere in the 5:xx range minimum. The other thing that you better think about is axles. What axles are you running? If you have an EB w/a D30 front (stock 66-70), you better think twice because it isn't a matter of "IF" but a matter of "when" you are going to be snapping axles. Even a D44 front axle (stock late 70-77) is pushing it hard with that big of a tire. And thinking along those lines as well, what transmission do you have in it? This all goes hand in hand and if you are building it to fit around a 38" or bigger tire, you better start out doing the right parts before you go big on tires. It is a whole lot easier to build big now than to realize that your truck isn't capable of handling what you intend on putting on it. If it were me and I was set on a set of 38" tires, here is what I would do:
D60 front axle w/5:xx gearing
Matched D60 or Big bearing 9" - 35 spline axle with matching gears
You have to think about parts breakage if you intend on mudding or wheeling.
D60 front axle w/5:xx gearing
Matched D60 or Big bearing 9" - 35 spline axle with matching gears
You have to think about parts breakage if you intend on mudding or wheeling.
s_bolt19 makes very good points but a lot of times uprading to Dana 60's isnt always an option, 38's will definately be ******* your axles, but as long as you wheel smart you shouldn't have many problems. Your stock diffs with aftermarket chromoly axles will hold up fine to moderate abuse offroad. I would use somewhere between 4.88 to 5.13 gears for 38's. A selectable locker will be a big help in keeping your axles together as well. If you get into a questionable situation you can turn it off to avoid breakage.
scrub
New member
How much lift do u have to clear 38's. What is the minimum lift required to clear if not worried about chopping out the feders? I was thinking of 37-38's on my 76 but my driveline is also stock.
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If you want 38's, you have to cut the fenders. Both front & rear and possibly some of the wheel tubs. The biggest tire you can get under the stock rear fenders is a 10.5 width tire. Most 38s are at least 12.5 wide, so cutting is essential. Most guys that run that big have a combo of both suspension & body lifts. Right now I run 5.5" of suspension lift & 33s and I still hit the front tire on the inner fender in a frame twister with fronts that are cut to use the Duff UFO flares. For a 38, I would go with a 4 or 5 inch suspension lift and add in another 1-2" of body. But it also depends on what you want, how far you want the tires sticking out of the wheel well. There are a lot of little things to factor in because of rim size & offset, actual tire size (Like I said, I run 33s but the true size when new was something like 32.4"), how high do you want the truck to sit, etc. You can do it with a smaller susp. lift, but it will require some creative cutting of all fenders. But if you don't want to get to crazy with the sawzall, I would do a combo of 4.5" susp. & 2" body lift.
bigbluebronc
New member
I run 38 s on my 75 bronco with 35 splines and a spool in the rear and 44 with chromolies shafts, about a 5,5 lift and a 2 inch body lift and fully cut fenders and no front inner wheel tubs. Actually thinking of lowerng it back too the 3.5 lift she feels kinda heavy in the rear, wants too go ass over but will rub the drivers rear wheel tub, just added a full hard top and that will make it worse, gonna put the full size spare out back on the bumper instead of in the back but as low as posible with out choking the departure angle too help hold her ass down! Oh np435 and j case and 4.56gears gets me 71 to 1 and would like a little more does that help!
