Automatic transmission problem...

[Broncobowsher]

@Speedrdr Higher stall helps but causes other things to be problematic.

As a side note, This is the kind of stuff we do in competition

I was in Bagdad playing on those same rocks the weekend before. I am going to say it is easier on a motorcycle.

 

[DirtDonk]

James, is it possible with your engine setup to lower the idle speed to something like 500 RPM? Some engines take that speed very well, while others don’t.
Not sure exactly what it would do to your problem, but it seems like it would be one step of several that might help.

 

[Yeller]

I was in Bagdad playing on those same rocks the weekend before. I am going to say it is easier on a motorcycle.

Until you put cones out telling you where you have to go

 

[Broncobowsher]

Until you put cones out telling you where you have to go

Not just cones, ribbons as well. And we have to use a clutch. You have it easy with those automatics and extra tires to keep you from falling over.

 

[Yeller]

Not just cones, ribbons as well. And we have to use a clutch. You have it easy with those automatics and extra tires to keep you from falling over.

You didn’t say trials riding! I have a huge admiration for you guys, the skill involved is spectacular. I used to go watch the nationals when they were at Disney OK

 

[rocknhorse76]

Way too much gearing and not enough brakes. Also probably not enough stall. Hydroboost is a huge benefit with an auto trans too. I run a 4R70W/Blackbox Titan/ NP205 with 5:13 gears in my rig, and rarely use low-low. Most of the time I use the 1.96:1 low range in the 205 so I can actually get somewhere. Once in a while I’ll shift the 205 into high and run the 2.72:1 low in the Blackbox. About the only time I use 5.33:1 low-low range is when I’m doing something really stupid lol. I also run about 2000rpm stall in my converter, which necessitates some big coolers, and I have D60 and 14B axles with huge brakes and HB to stop the thing.

 

[Broncobowsher]

You didn’t say trials riding! I have a huge admiration for you guys, the skill involved is spectacular. I used to go watch the nationals when they were at Disney OK

We had a round of nationals here this year. We even hosted a world round 6 years ago. Maine is slated to get a world round next year.
While a national round is great to watch, if you get a chance to see the top European riders it is amazing.

I just ride novice at local club events.

Back to the OP, what do you have for brakes?

 

[nvrstuk]

What Steve said in all his posts...

James... you aren't extinct and you'll get this figured out. lol What you'll figure out is what Steve said in the single digit posts ... you don't need the lower gears.

As you know I ran a ZF at 5.72, a 2.0 doubler and a 4.3 Atlas and 4.56 gears with 37"s for years. What Steve mentioned to me a LONG time ago was when I went auto was to try less gears. I setup my 4r with a Klune and Atlas. My TC came from a guy who told me YOU WILL NEVER STOP THIS THING WHEN IDLING in low, low gear. Well, he was right. I went HB immediately because my Bronco would just "Torque Up" and what a pain that was. Looked kinda cool when the LF corner lifted 5" tho. lol

Simple fix was QUIT using all the gears because that's why we have a TC, to modulate the "clutch" so to speak. Converter stall (like Steve said) won't help much unless it's so high that you are generating major heat.

I then went 3 yrs never engaging both low gear sets and realized that I never needed them both engaged at the same time in ANY situation.

So when I decided to go stoopid power for sand and super deep slushy snow I opted for a 3.0:1 Atlas (ProCase). It has just the right amount of low end gearing to allow you to idle up just about anything w/o increasing idle speed. I run my 464ci stroker at 700 rpm. Lopes like crazy and idles me up just about anything with the 4.17 first gear in the 6r (stock F150 converter) with 3.0 ProCase, 5.13 gears and 40"s. Perfect combo - least I think so- thanks Steve

Long winded answer for this: remove the doubler shifter for an entire trip. Problems solved.
You will not be revving up to 2K rpm to climb over some obstacle. Try it, it will blow ya away what the "modern day" torque converter will do for ya. Oh, HB helps a lot. Little bit of pedal and you are stopped. Also, you could/can lock in that TC in gear when dropping over an obstacle but I'm guessing the first couple times you will stall your' auto. It seems wierd stalling your engine when running an auto but it can happen when locking that TC. You won't need to when you have the HB.

HB really allows you to modulate the TC for climbing and dropping off a cliff face. Like riding a trials bike- keep the rpm's a little higher so you wont' stall it, so you have more power but control your speed with the clutch engagement. I do the same with my HB. Keep the idle maybe at 1,000 rpm on a knarly spot and modulate my speed with the HB pedal. Several ways to do it.

You'll like it James. Like Steve said, you just don't need those lower gears with an auto like you do with a manual- just not needed. Steve posted a couple of the real benefits of NOT being so low geared also.



(HB helps tho).

 

[Broncobowsher]

Going the other way (hypothetical) of too little gear, you will see that when you come up to something and you bounce back when you touch it. Then you throttle into it, get deep into the convertor stall (and the converter multiplication), rise over it and now you are too deep in the throttle. That loaded convertor unloads, the multiplication turns into straight speed, and you launch uncontrolled over the top. That is too little gear.

I like an auto with enough gear that it will climb at idle or a breath over idle and NOT get into the torque multiplication of the convertor. I would love to have a convertor modified for way low torque multiplication, 1.3 or 1.4 I think would be great with low gears.

I also love the lockup convertor in manual control. Long slow climbs and I can idle up without dropping a gear and reving the engine to the moon for no good reason or boiling the trans fluid from the high slip of running a higher gear. Lock the convertor and idle over stuff like a stick shift.

 

[nvrstuk]

Quote from above: ..." like an auto with enough gear that it will climb at idle or a breath over idle and NOT get into the torque multiplication of the convertor. I would love to have a convertor modified for way low torque multiplication, 1.3 or 1.4 I think would be great with low gears.

I also love the lockup convertor in manual control. Long slow climbs and I can idle up without dropping a gear and reving the engine to the moon for no good reason or boiling the trans fluid from the high slip of running a higher gear. Lock the convertor and idle over stuff like a stick shift." end quote



So many different ways of running a trail...

Allowing the converter (huge benefit in my book) to not be locked when idling up a "long slow climb" is what I like. Manual control of the auto like you said earlier is great and allowing that converter to modulate your speed over very rough terrain turns into a Cadillac ride (well, not exactly but much better)!!
Having the oonverter locked into 2nd gear lets say while idling over rocky or really bumpy terrain with your speed varying as the engine speed and actual mph speed is changed with load as you idle up to a bump, slow down, crest it, speeding up rapidly (like someone learning how to drive a stick shift) etc. It can cause a brutal ride. With the auto converter unlocked it greately reduces that abrupt, almost stop, then abruptly go as the rpms and mph increase over and over. Trans oil heat is not an issue. Stick a good cooler in and you'll never get above 160deg trans temps. I never have. At much higher speeds locking the converter for long grades can keep temps down but a larger cooler eliminates that need.

On my 6r I eliminated the switch to manually lock the converter anymore. I have programmed in my trans controller where I have blocked the converter from locking unless I'm in 6th gear travelling at 60mph or more. I used to use the manual lock feature in my 4r but quit using it after a while.

BTW- anybody that can ride a trials bike even in the novice class- yeah, you guys get my admiration too. I just got back into single track this year (from 50 yrs ago) and I can sure appreciate what you control and balance you have for your sport. Jealous and working on getting better but I have light years to go. lol