Gear Change for 37's on my 392

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MrJonnycat

MrJonnycat

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I went with Yukon gears, and I am running the 4.56s right now but I have actually ordered the 4.88‘s now. Decided I want to just a little more acceleration and a slower curl ratio. It’s only 145 RPM difference in 8th gear.
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texasbryan

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I went with Yukon gears, and I am running the 4.56s right now but I have actually ordered the 4.88‘s now. Decided I want to just a little more acceleration and a slower curl ratio. It’s only 145 RPM difference in 8th gear.
Interesting. So you felt that the 4.56 wasn’t quite enough? Did it at least get you back to stock acceleration?
 

Brosef

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picked up my 392 from having 37's and 4.56 gears installed. wish I could have done them sequentially to share impressions of them individually, but I can say unequivocally that it feels just like it did stock with 3.73 and 33's. it feels a touch more peppy from a dead stop, but otherwise it feels just like stock. at 70mph, the tach is right at 2k. I think the 4.56 choice was spot on.

went with Baja Boss M/T's (37x12.5 r17)
 

Outrun

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I went with Yukon gears, and I am running the 4.56s right now but I have actually ordered the 4.88‘s now. Decided I want to just a little more acceleration and a slower curl ratio. It’s only 145 RPM difference in 8th gear.
Crawling is too fast? 4.88's will be awesome but also see if a tune will satisfy. 505hp/tq would be easy.
 

MSparks909

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picked up my 392 from having 37's and 4.56 gears installed. wish I could have done them sequentially to share impressions of them individually, but I can say unequivocally that it feels just like it did stock with 3.73 and 33's. it feels a touch more peppy from a dead stop, but otherwise it feels just like stock. at 70mph, the tach is right at 2k. I think the 4.56 choice was spot on.

went with Baja Boss M/T's (37x12.5 r17)
Perfect. Now let’s see some pics! I’m planning on these same tires for my 392XR and a Clayton lift.
 
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MrJonnycat

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Interesting. So you felt that the 4.56 wasn’t quite enough? Did it at least get you back to stock acceleration?
Yes, I think it was pretty close to stock, but I want a bit more acceleration, and a better crawl ratio since I'll be wheelin this :)
 
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MrJonnycat

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Perfect. Now let’s see some pics! I’m planning on these same tires for my 392XR and a Clayton lift.
This was at the 4 Wheel Parts show Sat. My Jeep made it the farthest up the ramp for street legal rigs. Metalcloak rocks!!

IMG_7745.JPG


IMG_7746.JPG


IMG_7748.JPG


IMG_7750.JPG
 

MSparks909

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This was at the 4 Wheel Parts show Sat. My Jeep made it the farthest up the ramp for street legal rigs. Metalcloak rocks!!

IMG_7745.JPG


IMG_7746.JPG


IMG_7748.JPG


IMG_7750.JPG
Bad ass! Last question…did you have your wheels powdercoated? I’ve been trying to find a bronze set that best matches the 392 trim but am striking out so far
 
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MrJonnycat

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Bad ass! Last question…did you have your wheels powdercoated? I’ve been trying to find a bronze set that best matches the 392 trim but am striking out so far
Yes sir I did have them powder coated…… It was a prismatic powders color called Spanish gold

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houseofdiesel

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I'm running 37x13.50's on KMC XD 231 beadlocks, and want to re-gear for the bigger heavier tires. I'm thinking 4.56's, but wondering if I should do 4.88's instead?
Thoughts?
I am running 4.88 on my '68 Bronco with a 4.6 S/C Terminator on 40"s. Ran 46"s for Top truck and never had a problem. SuperDuty axles are far stronger than these axles but for 37"s I don't see why you'd need to low gears at all.

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