Dana 20 lower gearing

[jmms]

Has anybody done one of those gear reduction kits for a dana 20? If so what kit is the best for the money?

 

[Waverous]

Avoid the Terra Gears like the plague! A friend of mine owns a shop and says so far to date - he has replaced every set of Terra gears he installed. Customers woulod come in and request the gears and he would install them. Terra gear was more than happy to replace them, but he had to eat the labor costs on reinstalling them. After 5 sets in half a year, he now refuses to install Terra gears.

 

[Broncobowsher]

I have heard several bad things about the TeraLow gears. When I started checking what actually broke most people didn't know, they only heard that someone broke them. When I finally found a few people who broke them or at least knew what broke I started to figure some stuff out.<br><br>What was breaking was the welds on the planetary gearset. This threw off several alarms bells, mostly because Broncos with the D-20 don't have planetary gearsets. It was the 4:1 Jeep gears that were dieing.<br><br>I went ahead and got a set of 3.15 Bronco gears. They looked good, no signs of welded parts. This is definatly different then the Jeep Junk. I put them in and figured I should do some quick testing. Hubs unlocked and in low range I did a couple of heavy foot runs letting the auto quickly shift through the gears.<br><br>I pulled the transfer case off after about 500 miles due to an unrelated problem with the seal between the transmission and the transfer case.. Everything still looks good.<br><br>I am still waiting for someone to post that they personaly broke a TeraLow gear set in an early Bronco. (remember the Jeep stuff doesn't count) I don't recall anyone doing it. My foot is heavy enough that if it will happen, it will happen to me.

 

[swa0330]

I have heard that you can get lower gears for about $800, and I think it was the TeraLow's. I also read about the TeraLows breaking. When it comes to gearing, there are tons of ways to get lower. If you don't need an overdrive and want a manual tranny, get the NP 435. It just seems so expensive to regear a transfer case, when you figure that if you could save some money and suck it up, you could get an Atlas. I saw an Atlas/NV 4500 on eBay go for I think $3K. Not bad.

 

[jpoore]

Anyone used the Klune V? This seems like a nice solution, although pretty much the same as the Cold Duck in principle.<br><br>How about regearing other Ford TCs? I want a AODE, but the D20 kit is ~$500. The BW seems like a good unit (used in F-350s) if it could be geared lower.<br><br>Always scheming....<br><br><br>JP<br><br>

 

[Madgyver]

I think Tazz has a set-up going........<br>

 

[75]

ive been researching this same issue for some time and here are a few of my results. first we need to establish a common goal- lets say obtaining a final gear ratio of at least 45:1. im just gonna use my truck gearing for an example; 1st in c4 is 2.46, then tcase which is what we are working on, 3rd 4:11 rear end. i believe i am correct when i say LB20 is the lowest replacement gear set tera sells and its 3.15:1. so 2.46x3.15x4.11=31.8:1. not quite what we need . if all you wanna do rebuild your t case then your only option is jp rockeater gears the bcbronc sells. these have a low ratio of 4.86:1.throwing this in the fray 2.46x4.86x4:11=49.13:1. this is what is needed to do at least a little rock crawling. of course tons of other options exist and all require more$ and time. the JP is a rebuild and rebolt with no other drive train mods. the other things possible are klune, marlin crawler, tranny reagearing, diff regearing and on and on. if you want the simplest way to get 45:1 go jp rockeater. just my thoughts.

 

[Waverous]

[quote author=75 link=board=5;threadid=13591;start=0#102404 date=1043413684]<br>ive been researching this same issue for some time and here are a few of my results. first we need to establish a common goal- lets say obtaining a final gear ratio of at least 45:1. im just gonna use my truck gearing for an example; 1st in c4 is 2.46, then tcase which is what we are working on, 3rd 4:11 rear end. i believe i am correct when i say LB20 is the lowest replacement gear set tera sells and its 3.15:1. so 2.46x3.15x4.11=31.8:1. not quite what we need . if all you wanna do rebuild your t case then your only option is jp rockeater gears the bcbronc sells. these have a low ratio of 4.86:1.throwing this in the fray 2.46x4.86x4:11=49.13:1. this is what is needed to do at least a little rock crawling. of course tons of other options exist and all require more$ and time. the JP is a rebuild and rebolt with no other drive train mods. the other things possible are klune, marlin crawler, tranny reagearing, diff regearing and on and on. if you want the simplest way to get 45:1 go jp rockeater. just my thoughts.<br>[/quote]<br>I agree with 75. JP gears offer the best solution for the least amount of money AND modification.

 

[swa0330]

Yeah, but the JP rockeaters are over $1500. For just 300 more you can get a complete transfer case that's one of the most bombproof ever. Throw in the cost of "toughening up" the D-20 with a new output shaft and I say the Atlas II is a better choice for the same money.

 

[75]

[quote author=swa0330 link=board=5;threadid=13591;start=0#102425 date=1043418936]<br>Yeah, but the JP rockeaters are over $1500. For just 300 more you can get a complete transfer case that's one of the most bombproof ever. Throw in the cost of "toughening up" the D-20 with a new output shaft and I say the Atlas II is a better choice for the same money.<br>[/quote]Atlas 2 requires a 2 inch body lift-dude might not wanna do that.

 

[Broncobowsher]

Nothing requires a body lift, just a little clearancing of the under floor. Get out the BFH… ;D<br><br>Gears cost money, How low can you afford to go?<br>

 

[chuck]

You can't buy the 4.3 atlas for $1800. Also the driveshafts, crossmember, shifters and exhaust have to be delt with. None of that has to be delt with with the JP gears and you get 4.86 low.

 

[Rustytruck]

Yes but you have a rock crawler or a street truck and nothing inbetween. What is up with the Marlin system I hear about it but nothing more than a name. What is involved. If you have a stick with granny gear and the jp's you have it going but with an automatic your stuck with a second transfer case or something if you want to crawl rocks and do regular 4-low trails.

 

[Waverous]

As I said, JP gears offer the best solution for the least amount of money [glow=red, 2, 300]AND [/glow] modification.

 

[chuck]

my book only has the 1st and 5th gear ratio on the ZF so I can not give the ratios of the other gears (2-3-4) but from experance they are fairly even. 1st gear in the ZF is 5.72:1 so if you have the T-cast in high (1:1)you have 5.72:1, with the stock 3 sp 1st is 2.43:1 and t-case is the same so that gives you 5.9:1 and that is close to the ZF 1st of 5.72. I could go on and on but the bottom line is I think you can get about any speed/RPM you might want just by shifting gears.

 

[david heater]

I can speak on the "cold Duck" from Wh. with an Np 435 and the duck i'm at 160:1 with everything in low. Chuck said it before this is more then enough control i can idle up a lot where as before i was really hitting the go pedel. there is more then enough gearing.<br> As for the highway drag yes you do have that to contend with but I believe it is worth it. we are talking "rock crawling" after all..but you need to decide what you want your rig to do and at what sacrifices ( sp) .<br> As for modifications lets see. another hole in your tunnel for the extra shifter, new drivshafts, exhaust re-worked, a new rear output shaft.<br> the plus side, I have alot of gearing to choose from, both drive shafts are within 1/2" of an inch from one another. and the cool factor of being able to idle up rock faces and hear people say dammmm that is a really sick to be able to crawl like that.

 

[XT700]

Dave's 75--What size tire are your running with your combination? Also what is your R&P ratio? I'm building a Bronco with similar parts and need to make a couple more decisions on T-case and gear ratios. Thanks

 

[swa0330]

Dave is a friend of mine and I saw his rig last week in action. Believe me with his crawl ratio and wristed arm, in terms of crawling, his rig handled anything out there. All I was just saying earlier is that for $1500+ the JP rockeaters gears from BC are a bit pricey.

 

[75]

maybe if a few of us get together chuck might give us a deal of some type.

 

[david heater]

[quote author=XT700 link=board=5;threadid=13591;start=15#102735 date=1043507786]<br>Dave's 75--What size tire are your running with your combination? Also what is your R&P ratio? I'm building a Bronco with similar parts and need to make a couple more decisions on T-case and gear ratios. Thanks<br>[/quote]<br> I'm running 35 now but I plan on going up too 36" maybe 37". RP ratio right now is 4:10.