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Dan Pitts
Body Lift
Posts:232
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| 07/02/2007 8:51 PM |
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| so i just got my truc back together and we went out for a test run everything is good but when i am in high i just dont got enough balls even with a built engine. the thing is that when i go to low the gears are so low that when i give it gas to pick up speed i got to shift and it is always right at the bottom of the hill and i cuts out. there is no gradual increase in speed. it is either slow or extremly fast that it tachs out with a push of the pedal. how do i fix it i am thinking about putting 5.29s in it which it will take me back to a little lower than stock. i just need a little info on what to do. |
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Danny Pitts
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lift it, fat chicks can't jump |
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fourwd1
Street Queen
Posts:57
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| 07/03/2007 7:41 AM |
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| And we just need a little info to answer.
What engine, what tranny, what size tire, what's your current gearing ????
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- as seen in Four Wheeler magazine July 2006, Off-Road magazine Feb 2007
'84 4Runner SR5 - ARBed 5.29's F&R, 4.7 & 2.28 t-cases, drv trn lift, Chevy's, 30 spline Longs, BudBuilt skid, 36" TSLs... |
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Dan Pitts
Body Lift
Posts:232
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| 07/05/2007 8:26 PM |
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| i got 4.10 in the rear end. stock engine bored 0.60 over with ported and polished heads and a comp cam with a weber carb. stock trany and transfercase but the tcase is 5to1 with and 33 inch tires.
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Danny Pitts
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lift it, fat chicks can't jump |
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SnoMan
Lift & Lockers
Posts:943
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| 07/06/2007 5:33 AM |
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quote:
Originally posted by Dan Pitts
i got 4.10 in the rear end. stock engine bored 0.60 over with ported and polished heads and a comp cam with a weber carb. stock trany and transfercase but the tcase is 5to1 with and 33 inch tires.
Install the 5.29's you will not regret it as they will play well off road. They should be a good match for your tire size and engine off and on the road and increase over all performance a noticeable amount. |
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Visit the SnoMan at
www.thesnoman.com |
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fourwd1
Street Queen
Posts:57
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| 07/06/2007 5:38 AM |
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| If you're running 33" tires now, you don't want 5.29s unless you plan on going to 36" tires real soon. If you plan on staying with 33s, 4.88 gears would be a better choice if you do a lot of highway driving. |
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- as seen in Four Wheeler magazine July 2006, Off-Road magazine Feb 2007
'84 4Runner SR5 - ARBed 5.29's F&R, 4.7 & 2.28 t-cases, drv trn lift, Chevy's, 30 spline Longs, BudBuilt skid, 36" TSLs... |
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SnoMan
Lift & Lockers
Posts:943
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| 07/06/2007 6:23 AM |
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| If you are going to go through the trouble of re-gearing, go to the 5.29's as the rewards are greater and it gives you room to grow if you want too. It is always better to error to a little deeper than you need than less. It should run sweet with 5.29's and a few extra RPM will not hurt anything and they will reduce average drive line torque loading too on drive shafts, Tcase , tranny and engine |
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Visit the SnoMan at
www.thesnoman.com |
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webby4x4
Forum Admin, Magazine Editor
Rock Star
Posts:2375
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| 07/06/2007 6:39 AM |
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Danny - if you're 5.0:1 in the TCase, you should have TONS of low gearing for off-roading, and unless you've change your wheeling style since I left Indianapolis, you're more into rock crawling than trail riding (4Lo vs. 4Hi).
That said, keep in mind that the R&P gears in the stock Toyota axles are not super strong, and the deeper the gears, the weaker they get.
Let's do the math here though...
Your truck has a W56 5-speed, top-loading transmission with the following gear ratios:
- First Gear: 3.954:1
- Second Gear: 2.141:1
- Third Gear: 1.384:1
- Fourth Gear: 1.00:1
- Fifth Gear (OD): 0.85:1
To calculate your compound gear ratio, simply multiply your 1st gear trans gear times your t-case gear, times your axle gear ratio...
3.954(trans) X 5.0(t-case) X 4.88(gears) = 96.5:1
3.954(trans) X 5.0(t-case) X 5.29(gears) = 104.6:1
If your primary goal is rock crawling and some more difficult trail riding, etc. - then you should be shooting for somewhere around 85:1 - 95:1 compound gear ratio. At this ratio, you should be able to put your truck in Lo-Lo, jump out, and walk past it slowly… 90:1 is pretty darned low.
If you're going to be doing some really extreme rock crawling, then your goal should be slightly deeper. This is all based upon a manual transmission, as calculating your optimal compound low range for an automatic is different.
Now, let’s calculate what your probable RPM’s are at 65 m.p.h., using another calculation, based upon 33” tires, then upon 35” tires, while swapping between 4.88 and 5.29 gear sets…
33” Tire, .85:1 final gear trans, 65 m.p.h. and 4.88:1 gear ratio = 2,745 RPM’s.
33” Tire, .85:1 final gear trans, 65 m.p.h. and 5.29:1 gear ratio = 2,976 RPM’s.
35” Tire, .85:1 final gear trans, 65 m.p.h. and 4.88:1 gear ratio = 2,588 RPM’s.
35” Tire, .85:1 final gear trans, 65 m.p.h. and 5.29:1 gear ratio = 2,806 RPM’s.
Now, knowing that you have a 22R engine, they tend to make more power in the higher engine rpm range, than say an engine with a longer stroke and a bigger bore (e.g. a torque-ier motor), so you’ll want your RPM’s at 65 m.p.h. to be around 2,800 rpm or so, otherwise you’ll be drinking gas through a fire hose.
IF, you’ll be trailering your rig and not driving it on the street then the decision becomes quite easy… go deep, but not so deep that you can’t really wheel it. Remember, it IS possible to go TOO deep, and don’t forget that getting around 5.29:1 gears is getting to a range where I’d start to question the strength of the gear sets if you’re doing some hard-core rock crawling.
Hope this helps.
Rick
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Rick Webster
Editor, 4X4REVIEW.COM - A Tork Media, Inc. Publication
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'74 FJ40 Land Cruiser
"Measure once, cut twice" |
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SnoMan
Lift & Lockers
Posts:943
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| 07/06/2007 8:47 AM |
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quote:
Originally posted by webby4x4
Remember, it IS possible to go TOO deep, and don’t forget that getting around 5.29:1 gears is getting to a range where I’d start to question the strength of the gear sets if you’re doing some hard-core rock crawling.
I really do not think gear strength is a issue here with this drive train. A 5.29 would have a 37 tooth ring gear and a 7 tooth pinion and would have good tooth thickness and strength. A 4.88 would have a 39T and a 8T and not offer anymore real strength. THere is a lot of formulas for gear ratios but while some attempt to more or less match RPM of old stock tire and combo, it is not the simple and engine size plays a role here too because the drag or 33 or 35 cruise take a greater percentage of available power with a 4cyl 4x4 than one with a big V8 so you are best to hedge you bet by being a little deep. ALso it is going to take a lot more than 5.29 gears with 33's to start eating a lot of gas. Actually it might even get you a little better MPG cruising than 4.88's because you will have to down shift less and up shift sooner as well. Your tires and lift will have far a bigger negative impact on MPG than 5.29 gears will. BTW, if this was a V6 truck I would not be considering 5.29's at all. The 22RE is a good motor that does it best work at around 3000 RPM and above and deeper gears will keep it in that RPM range better. The secret to a good running 4x4 with a 4 banger is deep gears to keep RPM's up to better extract usable power. Think of it this way, when you want to remove a stuck bolt and need more force you might use a 1/2 inch drive breaker bar instead of a smaller 3/8 inch drive. Same basic thing with deep gears vs taller ones. |
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Visit the SnoMan at
www.thesnoman.com |
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Dan Pitts
Body Lift
Posts:232
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| 07/06/2007 1:58 PM |
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| this helps a whole lot guys. i think i am going to go ahead with the 5.29s i was up in the air about them but now i am sure will i still have enough power with the 5.29s if i upgrade to 35s which i will be doing soon. i wonder though i i up grade to a bigger tire and lower gears is it goint to break a berf easier. since most of the stress will be in the axle shafts and the berfield is a lot weaker. yet agian i am not to sure about this. this is just me thinking. |
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Danny Pitts
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lift it, fat chicks can't jump |
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webby4x4
Forum Admin, Magazine Editor
Rock Star
Posts:2375
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| 07/06/2007 2:39 PM |
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| ummm... yeah. Don't hang your hat on those Birfields dude. Even though they're the larger, stronger versions, they'll fold like a cheap lawnchair. |
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Rick Webster
Editor, 4X4REVIEW.COM - A Tork Media, Inc. Publication
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'74 FJ40 Land Cruiser
"Measure once, cut twice" |
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SnoMan
Lift & Lockers
Posts:943
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| 07/06/2007 5:22 PM |
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| As long as you do not put a locker up front the Birfield should hold up even with 35's. If you put a locker in up front, all bets are off. |
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Visit the SnoMan at
www.thesnoman.com |
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webby4x4
Forum Admin, Magazine Editor
Rock Star
Posts:2375
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| 07/06/2007 5:35 PM |
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Right up until you turn the wheel full lock and give it some gas... the tulip will seperate and the carnage will be catastrohpic. I've seen it at LEAST 15 times, and experienced it once.
Here's another big nasty about Birfields... it's a 2 hour fix on the trail, at least. With a regular u-joint, you can have them swapped in 20-25 minutes. But I'm way off topic here. [:D] |
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Rick Webster
Editor, 4X4REVIEW.COM - A Tork Media, Inc. Publication
- - - - - - - - - - - - - - - - - - - - -
'74 FJ40 Land Cruiser
"Measure once, cut twice" |
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