Shifting on the Fly and Stalling at Stop Signs

[jmarkel]

I have two questions about my Jeep. My 8 has the T5 and Dana in front of a 258 with 4.0 Head.

1. Should I be shifting this on the fly in and out of 2H and 4H? Today I was driving about 50mph and then I came across this horrible drift. I immediately pushed in my clutch while in 5th gear and slapped my dana into 4H. No issues going in. Drove for about a mile through the drift and back to pavement and put it back into 2H. Would shifting like this do any damage to anything? I seem to be able to shift it in and out without any difficulty. Afterall, it only has 51K on it.

2. I installed a new Holley 390 cfm. It runs and drives fine. However, today was the first time I had it on the interstate since installation. After 30 miles and stopping at the exit, I stalled. Never stalled before and not since. ANy ideas?

Thanks

Jarred

 

[John N]

I don't think the Dana 300 transfer case was ever ment to be a "shift on the fly" like some of the newer models. You must have been luckey on the shifts you made at 50mph. I only shift mine at a stop or a slow roll.

 

[IN2JEEPN]

Shift on the fly!!!!

Were your hubs already locked???
I wouldn't do that too many times!! You were just lucky!!!
I've seen Dana 300's Bust from doing that.

 

[BIG_Mark]

You CAN shift on the fly but as stated above you are asking for trouble doing it at highway speeds, even with only 51k on the rig.

When I shift on the fly its never at more than 10 mph.

 

[jeepnmatt]

i'm going to go across the grain on this one.

i don't see any reason you cannot shift into and out of 4WD HI "on-the-fly" as long as your front hubs are locked in, your rear tires are not slipping, and you are going straight. with your hubs locked and the rear tires not slipping, the front driveshaft and the gears associated will be spinning at the same speed as the rear. as long as it shifts smoothly, you shouldn't have any problems since everything is "synchronized". i've been doing it for years with never a problem. commonly i would pop it into and out of 4WD HI while on the interstate.

you must be moving very slowly to shift into 4WD LO.

don't know about the carb.

matt

 

[Jeeper 4]

I owned a 81 Scrambler that I put over 300,000 miles on. I left the hubs in the year round and shifted on the fly at any speed as long as my rear wheels weren't slipping.I never had any problems and never had to do anything to the transfer case except maybe a seal or two. Even learned to shift from H to L and L to H on the go but that required getting your RPM's just right to avoid grinding.

 

[tom keyes]

176,000 miles on a 81 CJ-8 and living in the Colorado Rockies I shift on the fly only after I lock the hubs. I don't leave them locked all 365 days of the year though. Only lock them if it looks like a day where you are going to get to shift into 4 wheel drive and then Un lock them when you go in at night. Unless it is still snowing out. I have had wheel bearings and hubs go out from leaving them locked full time on other rigs. Why put the extra stress on the parts when you don't have to. Save the money and buy a extra tank of gas to get you back home from a adventure with your Scrambler???

Good luck, And you really need to know and love your 8 before I would sugest shifting from high to low on the fly. RPM's are everything. Unless the cliff your heading for looks really bad.

TK