Losing my mind! BB or BD

[5280Bronco]

Leaning towards BD, but wish you could get the hard top headliner with the 2.7.

I was able to build a BD with the headliner and the 2.7. 4 door.

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[dgorsett]

I have been going back & forth on BB or BD also with the different gearing being my sticking point. I have been studying all the comments and googled the hell out the gear differences as I have no experience with choosing this. If anyone sees a flaw in my gearing conclusions please let me know.

I will do mostly street driving and am just getting into off road fun, so I expect either choice will do what I need. Leaning BB for gearing. BD seems like a great package for anyone going off road at all with steel rear bumper, MGV, washout floors and I like the basic steel wheel look also.

BB offers 3.73 or 4.27 with the 4.27 feeling like a sweet spot, get a little more torque for low end performance around town and also better than 3.73 for off road, without going to 4.46 which would cost in mileage. Clearly 3.73 is best for mileage and I am looking for the best of both worlds. I am going with the 2.7 and 10spd and think the tranny overdrive may make the 4.46 & mileage on the BD not a problem from what I read here.

I like everything about the BD, would have to move up to the 4.46 gearing though which makes the truck more off road worthy and gas mileage takes a hit with rpms running higher around town. Daily driving will be around town & wouldn't mind getting best mileage possible since this is most of my driving, that being said still want to be off road capable and not under geared if I want to challenge the truck.

Please provide any thoughts on what you feel is the best of both worlds gear or if I am looking at it wrong and should gear for the way I drive most of the time.

I found this chart which shows performance in rpms at 65mph using the BD tires size.
If you change to the BB tires size the rpms went down about 40 rpm give or take.
at 65 mph 3.73 rpm 2577
at 65 mph 3.27 rpm 2951
at 65 mph 4.56 (close as the chart gets to 4.46) rpm 3151

Gear Ratio / RPMs for New Tire (@ 65 mph)

2.35	2.73	2.94	3.07	3.21	3.31	3.42	3.55	3.73	3.91	4.11	4.27	4.56	4.88	5.13	5.29	5.38	5.71	6.17	7.17
1624	1886	2032	2121	2218	2287	2363	2453	2577	2702	2840	2951	3151	3372	3545	3655	3718	3946	4263	4954

I think your chart assumes a 1:1 transmission high gear. Broncos will have a 0.65:1 OD gear, so knock 35% off your rpm's. Really you won't notice the difference in 4.27's or 4.46's (Less than 5%). And mpg difference will be imperceptible, may even be better with the 4.46's. Now I'd say stay away from 3.73's if you're going over 32 inch tires and 4.70's if you're going less than 33's.

 

[Rover72]

I think your chart assumes a 1:1 transmission high gear. Broncos will have a 0.65:1 OD gear, so knock 35% off your rpm's. Really you won't notice the difference in 4.27's or 4.46's (Less than 5%). And mpg difference will be imperceptible, may even be better with the 4.46's. Now I'd say stay away from 3.73's if you're going over 32 inch tires and 4.70's if you're going less than 33's.

Good info! Yes, sticking with stock 32 tire size. I wont go where the stock 32's can't take me. If I find myself wanting to climb something that needs bigger tires will trade the truck for a taller machine or figure out if upgrading the BD can be done cost effectively.

The tranny part I did not know and had suspicion though. I figured Ford had to make the stock tires & gearing for each model they were offering on the B&P work both on road and off road and figured going up in gear just tilted the spectrum more towards off road not causing to much loss on the other end. The rpm's on the chart for 3.73 (2577rpm+-) to the 4.46 (3125rpm+-)were like roughly 20% different, causing me to think performance change might be significant. Your correction in OD balances things out.

I read somewhere about starting with the crawl ratio and then working from that number forward and it was lost on me not knowing gearing and trying to find the pieces. It has been interesting learning a bit and nice to get help. Thx

 

[PowPow]

btw, this video is what gave me the idea of the pods on the front bumper as fog lights:

about 2mins in.

 

[Studawg]

I just hate cloth interior. If BB had the vinyl, I’d be open to it. But then the BB also comes with that awful rear bumper.

 

[mrjerry469]

I keep going back and forth BB and BD I should just download the BP been on it soooooo much. I'm thinking about putting in another reservation now for my daughter.

 

[Hkak45]

And I’m certainly not paying $650 for those pod lights. I’ll buy the 6” KC slims for half the price.

The great thing about BD is it comes standard with the aux switches too so makes it easier to do a clean install on any light you want to put there. The price Ford charges is hilarious but they will still sell a ton of them.

 

[mdepll]

The issue with BD is the high cost. For us Canadians you are into the mid-high 60s. That’s expensive for a rugged, practical off roader.

 

[NotAnonymous]

The issue with BD is the high cost. For us Canadians you are into the mid-high 60s. That’s expensive for a rugged, practical off roader.

What are you aiming for instead (at a lower cost)?

 

[Rivelife]

I doing either BD or BB 2.7 sqauch, the BB grill is the best looking one IMO and had has me wanting for that reason but i want the MGV of the BD,

 

[NotAnonymous]

I doing either BD or BB 2.7 sqauch, the BB grill is the best looking one IMO and had has me wanting for that reason but i want the MGV of the BD,

I'm in the same camp, albeit non-Squatch - I've gone back and forth between BB and BD for months and still haven't come to a conclusion.

 

[drive21bronco]

Yea just a week before the order banks opened I realized you could get the advanced transfer case on the BD so that’s what solidified it for me. I do like the signature lights. May try to add those later.

 

[Headsong]

Yea just a week before the order banks opened I realized you could get the advanced transfer case on the BD so that’s what solidified it for me. I do like the signature lights. May try to add those later.

I think it's Headlight Revolution? That will have something.

 

[Roger123]

For me the availability of the Advanced 4x4 on BD sealed it up. That was an important option. RWD short wheel base SUV's can be a handful, advanced 4x4 takes care of that.

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