crawl ratios?

jeepcj3a

Well-Known Member
Joined
Jul 13, 2006
Location
winston salem
gearing question: for places such as tellico/ure/callantee, ect. on the east coast, what are most of yalls crawl ratios?

im looking at 2 setups and am going to base my decision on the crawl ratio that ill get.

either 85:1 with toyota duals and stock gears or 43:1 with a dana 300 and stock gears.

will be $400 less to go with the dana 300 over the duals. however i can only upgrade to 4.1 instead of 10.1 in the future with the duals. although i should be able to fully clock flat the 300 and get a flat belly.

Im fairly new to offroading, only gone out a few times and want to set up the drivetrain correctly hopefully the first time.

specs: toyota pickup, 4.3/th350/?, 4.37 and 37's

yes this is newb, but im hoping to get more responses in this section than the newb tech.
 
yeah, i messed that up, i did 3.76 for the th350, 2.62 for the dana 300, and 4.37 for the axles and i get 43.1, not 70:1, not sure how i got that.
And its 85:1 for the duals with stock gears.
 
I get 54:1 with the TH350 and dual yota cases. I had a single case but with 4.7 gears behind a V8 and an auto that made as much power as your average V6, and it worked VERY well with 38's, crawl ratio was about the same.

Personally, I don't see the need for dual cases with an auto - the torque convertor takes up alot of that middle ground. A single 4.7 case would be just fine, and about the same price (gears vs. doubler and another case), but cheaper overall in the end.

And you can clock a single yota case to get the flat belly, that's not an issue. it'll also be easier / cheaper to make driveshafts if you run a Toy case, and the Toyota u-joints are quite a bit stronger than 1310's.
 
jeepcj3a said:
rich, did you have any problem with the front drive shaft fitting around the th350 oil pan with the single case clocked?
Click to expand...

I ran a 2-piece shaft since my driveline was going to be ~50" long, but it's doable. The P/O of the 700R4/Toy case combo ran a 1-piece shaft.
 
jeepcj3a said:
gearing question: for places such as tellico/ure/callantee, ect. on the east coast, what are most of yalls crawl ratios?
Click to expand...


I ran mine for awhile at ~41:1 with 33's...

then swapped diff gears and ran ~50:1 with 33's, then moved to 36's...

now I run ~79:1 after swapping in the Atlas, and still running 36's...

I prefer the current setup for places like Tellico and Crozet...but any of them were fine for UNF or Callalantee...

granted, it's with a 5-speed and the Jeep 4.0L, so not a direct comparison...


Greg
 
well ive decided that duals with 4.7 rear wouldnt be worth it, so now its down to stock duals, or just one case with 4.7, or one dana 300 then once money allows, go to 4.1 gears.

I guess in order to narrow it down even more, for a novice wheeler like myself, would i ever really need to go to 2.28 instead of 5.19(ie, is it worth having duals so i can choose b/t 2.28 or 5.19), or would i be fine in 1:1?

thanks
 
i would go with dual cases instead of a single case with 4.7s. if you want lower gears after that then put in the 4.7s. the gearing options you get with the dual cases is hard to beat.
 
X2. I drove several rigs with single cased 4.7 setups. Didn't care much for them. Sometimes it was to low and then other time's I felt I wanted to be a little lower. After running my old rig with duals and now having the 4:1 in my TJ, hands down I'd take the dual setup over the single 4:1 anyday. Same situation. Sometimes it's to low and other times I wish I had more.
 
He's running an AUTO. duals with 4.7's in the rear case = not going to be able to stop.

With a manual trans, I whole-heartedly agree on duals. Josh I know for a fact yours was a stick..

You can't compare the 2 from my experience in having a 53:1 manual, and then a 59:1 auto.

You could go duals for the flexability, but you're making for a long drivetrain (and therefore, a long, rock catcher front driveshaft, but you will very likely have issues stopping if you go double low with the 4.7's in the rear case.
 
X-whatever on the duals with a manual. I have 4:1s in my 'case and I'd love to have an "in-between" instead of ragging out low-range or lugging it in high-range. Total crawl on mine is 65:1 with 32"s.
 
So Rich, what would you say is too much crawl (in terms of stopping)?

I'm working on 54:1, but was considering the ability to get 88:1 with dual cases and 3.42's in the diffs (still street-driven so I can almost make a highway gear).

BTW, SM465 and 205 with 4.10's in te works and I may have a 203 coming (FREEBIE), and would re-gear to numerically lower gears with the doubler).

Also, with the doubler setup I'm thinking about there's not much reduction in the diff at 3.42, so that means the d-shafts are seeing a lot of torque (vs. rpm); so would I be worried about constantly twisting shafts and spitting joints?
 
With a 1" bore MC, minitruck booster, FJ60 4-pot calipers front and Monte Carlo calipers on the rear, I would bottom the pedal trying to stay stopped at 59:1 if i was pointed downhill much at all.

If I knocked it into Neutral, it would hold just fine, and stopped well.

Level ground was OK, but you could tell the rig was pushing against the brakes.

I never once wanted for a lower crawl with the auto. I frequently found it to be almost too low. But that's what second gear is for.. :)

Torque converters are a beautiful thing.

On a manual trans, I frequently wanted ALOT more than 53:1.. 100:1 or more, and the flexability of dual cases would be great.
 
CrashKnott said:
So, what would you say is too much crawl (in terms of stopping)?
Click to expand...

I have no trouble stopping my 205 crawl. Manual trans running discs front and drums rear with the E350 master cylinder I can stall it out in 1st gear. I have never wheeled an auto so I can't speak to that but I have NEVER had to low a crawl ratio to suit me. Rode with a fellow at the SFWDA convention that had a 340 crawl in a CJ with a D300 and a KluneV, he seemed to have no problems stopping either eventhough sometimes it looked like he was stopped :) My experience would advise going with the lowest crawl ratio you can reasonably afford.
 
well i just bought a th350/adapter/toy case and am going to put in marlin 4.7 gears so i should end up with around 77:1 which i think should work well
 
jeepcj3a said:
well i just bought a th350/adapter/toy case and am going to put in marlin 4.7 gears so i should end up with around 77:1 which i think should work well
Click to expand...

That's 52:1.. 2.52 * 4.7 * 4.37 ;)

Outta work very nicely.
 
Rich said:
That's 52:1.. 2.52 * 4.7 * 4.37 ;)

Outta work very nicely.
Click to expand...

oh, i was just multipling the auto low gear by 1.5 just becuase the calc on novak said that you can safely do that because of the torque converter, so thats how i got 77:1.

should you not multiply the auto low gear by 1.5-2 because of the torque converter? or does the torque converter not really make a big enough difference in the crawl ratio?
thanks
 
Well, the whole number thing is kinda iffy anyway, since it's a fluid coupling.. you can go slower than a guy with a manual and 150:1, soooooo... what's that tell ya.

I just try not to compare the 2 directly. Only autos to autos, manuals to manuals.

Different TC's will also act differently...
 
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