Dan Wheeler's 69 4R70W/Atlas Build Thread

[DanWheeler]

maybe I'll just go with the 5:1 instead of the 6:1 then. I dont want to go 4.3 and wish I'd gone 5. I really like the novelty of going EVA while rolling over an obstable and making everyone laugh.

3.8:1 Atlas = 105:1 crawl
4.3:1 Atlas = 120:1 crawl
5:1 Atlas = 140:1 crawl
6:1 Atlas = 166:1 crawl

With BroncoGraveyard pricing I actually save $10 when I go up to 5:1 compared to the 4.3:1 w/ 32 spline front output. So.. you know... anything to save a few bucks.

 

[DanWheeler]

Ditto, except I'd go with the 3.8:1. You better have good brakes with any higher, because you won't be able to hold it back unless you shift to neutral. AA recommended the 3.8 to me for a 4R70W for that reason. Now that I've run several trails with my 2.0 NP205, I'd say you'd have too big of a gap in gearing except for the most extreme sections of a trail. 2.0 gets the job done well on 90% of what I would consider moderate to difficult trails. With 5:1 or 6:1, you'd only be able to use 4L in the toughest of situations. You'd be way too low for everything else and too high in 4H.

It's why I haven't taken the plunge on the Atlas. I'd miss the 2.0 low range for 90% of the trail. I'd really like the 3 speed mini STAK and would probably pull the trigger except for the lack of mechanical speedo option. The Stack mini 3sp is approximately the same dimensions as the Atlas II for not too much more $$.

oh you guys are ruining all my fun making me think about all these important factors.

 

[av8rds]

It's time to purchase the Atlas. I'll be purchasing from PolyPerformance unless someone can recommend a retailer with a better price.

Kincade Bauer all day long

 

[av8rds]

oh since your considering different ratios and I'll add, if you havent looked at it you should consider the 4-speed.

This past weekend I was out using 4low(3.8)/2nd gear and found it wasnt working well, too low, not enough whee speed, ended up going to to 4med(?)( 2.7) first/second and found it about perfect.

And much to people who say(not in this thread) you cant use 150:1, I have and do(with a 4L60e 3.06:1 first). I love it. Cant/dont use it every time out but I love it.

I bought the 4sp as I wanted the 2.7 for the beach stuff I do, 3.8 for the rocks and the 10:1 was just a bonus, a bonus that has made me very happy.

Kincade got me the 4sp for about what everyone else was advertising the regular 2sp for. I dont know if its the same way today but I wouldnt change a thing, best mod I have done to my bronco.

 

[DanWheeler]

the 4 speed adds quite a bit of length doesn't it? I think i'm pushing the rear driveline angle with the 4R70W/Atlas w/ short tailhousing as it is.

 

[DanWheeler]

Kincade Bauer all day long

well his phone is dead and he doesn't answer his email (already tried last week) so I doubt I'm going to buy a $2000 transfer case from someone I can't get in touch with.

 

[Socal Tom]

I would go with the 4.3 or the 5. With 4.3 you end up with the following final drive ratios ( with rounding)
60,33,21,15, 14,8,5,3
With the 5 you end up with
70,38,24,17, 14, 8,5,3

The big difference for me is that with the 4.3 you have one gear that's basically the same between high range and low range. with the 5:1 you don't. With the 5:1 you will spend most of your time in 2nd or 3rd with the 4.3 you will spend most of your time in 2nd.
Remember with an automatic, you want to keep the RPMs above 1500 to keep the tranny cool as you head down the trail I spend most of my time in low range 1st or 2nd to make that happen.
Tom

 

[lars]

Kincade Bauer all day long

X2 on Kincade. AA shorted me a couple of parts, and later when I was trying to stop a leaking speedo drive seal, he was tirelessly helpful.

 

[lars]

well his phone is dead and he doesn't answer his email (already tried last week) so I doubt I'm going to buy a $2000 transfer case from someone I can't get in touch with.

Well, maybe not then. Hmmm.

 

[av8rds]

well his phone is dead and he doesn't answer his email (already tried last week) so I doubt I'm going to buy a $2000 transfer case from someone I can't get in touch with.

huh, must be having some problems then......but if he does get in touch, hes the man.

 

[av8rds]

the 4 speed adds quite a bit of length doesn't it? I think i'm pushing the rear driveline angle with the 4R70W/Atlas w/ short tailhousing as it is.

mmmm I dont think its any longer than my 4L60e and atlas 4sp with no short tailshaft, I could be wrong

edit: according to Novak mine is 21.9" long

 

[av8rds]

actually the 4R70W is 20" so you'd be a touch shorter than mine

 

[DanWheeler]

actually the 4R70W is 20" so you'd be a touch shorter than mine

So how is your rear driveline then? I'm a little worried about my angle. Do you have high pinion? Extended wheelbase? low lift?

the 4R70W is 27" w/ 4x4 tailshaft. The Atlas II w/ short tailhousing is 11.8"

 

[av8rds]

hmm I got the numbers here using the 'B' dimension. My Atlas bolts up at the end "b" right to the 4sp no adapter.

The only thing I did for driveshaft angle is cut and weld new perches for a better angle at the pumpkin.

oh and 4.5" lift and no extended wheelbase.

 

[av8rds]

there is some good pictures up here

 

[DanWheeler]

hit the junkyard on Friday to look for 90s Explorer 1310 CV driveshafts. Sure enough! (only the fronts are 1310CV)

It's just a few inches shy of my stock rear shaft. Should be a good candidate to cut down to use for my front driveshaft until I can afford a heavy duty, full spline shaft.

 

[bighorn]

hit the junkyard on Friday to look for 90s Explorer 1310 CV driveshafts. Sure enough! (only the fronts are 1310CV)

QUOTE]

That's interesting. What's the tube diameter on that driveshaft? I have heard of people using the front driveshaft out of a 90's Jeep Cherokee b/c of the 2" tube diameter and needed clearance for the front driveshaft vs the pan.

 

[DanWheeler]

That's interesting. What's the tube diameter on that driveshaft? I have heard of people using the front driveshaft out of a 90's Jeep Cherokee b/c of the 2" tube diameter and needed clearance for the front driveshaft vs the pan.

i'll take some measurements and let you know. I'd like to see whats under that boot too. I'll get some measurements on spline length and travel as well.

 

[DanWheeler]

Here is some info and pics of the Explorer driveshaft:

New Wild Horses rear driveshaft:
Upper tube diameter = 2"
Lower tube diameter = 1.6"

My old Spicer rear driveshaft:
Upper tube diameter = 2.5"
Lower tube diameter = 1.6"

90s Explorer front driveshaft:
Upper tube diameter = 2.125"
Lower tube diameter = 1.825"

More pics of 90s Explorer front driveshaft:

 

[DanWheeler]

here's a pic of the new (not remanufactured) starter I got from 14Rebuilders on Ebay for about 50 bucks. I'm a little skeptical but if it works as well as it looks then I'll be in good shape. Apparently they are made in USA not China.

http://myworld.ebay.com/ebaymotors/14rebuilders/