Saturn Overdrive Towing Capacity

Hello,
I have a new manufactured Saturn overdrive in my M38A1. I'm running the F134 and 5.38 axles. Where I live we don't have real hills.
The manual for the overdrive cautions against towing "heavy loads" with the overdrive engaged. I'm wondering how heavy is heavy. My David Bradley trailer probably weighs 600 lbs with a couple bags in it. Does it seem reasonable that I could tow that with the overdrive?
Thanks,
Ken

 

I don’t know if in a short wheel base, under powered, under braked, over geared Jeep you want to tow anything at a speed where an overdrive would be beneficial or safe..
you would have to be on some really strait and flat road to want to engage it.. Prob aren’t going to do any damage being in the weight range if the Jeep...

 

Excepting steep downhill grades your F-134 will almost never have enough power to engage the O.D. if pulling a trailer.

 

Contrary to what others are saying, I use my OD more when my trailer is hooked up. Really helps to have the "in between" gear when RPMs aren't quite right with the trailer. Off road, 1st gear 4 lo with OD is a godsend so you don't have to leave the unsynchronized gear. From the literature I saw, they are rated to something like 350hp, so we have nothing to worry about.

 

Have pulled my Jeep trailer to Colorado and back several times pulling my Jeep trailer.
Both with F4 and V6.
No problems and no worries.

 

and...folks were pulling their 15ft travel trailers behind their Jeeps in the 60's....using an overdrive.
I saw it all from the rear seat.

DISCLAIMER: These were Warn overdrive units.

 

I wouldn't worry about the Overdrive getting hurt with the 134 so long as you drive it responsibly. Your limited by horsepower and brakes.

If it were a v6 I would keep it out of overdrive for the long haul. Heat is the enemy so a short stretch between gears is different than pulling a sail at 80mph

Remember these are cooled by the spit off the transfercase gears. Not pressure lubrication with filters and coolers.

 

Thanks for the replies. I'm not talking about cruising down the highway at 60 mph. I prefer to cruise at 45 mph, maybe 50. With my tires I'm pulling 2700 RPM at 45 without the overdrive. With overdrive it's about 2000. The engine seems much happier and I still have plenty of throttle left. The 5.38 axle with overdrive isn't far off the 4.27 in direct drive, which was an option with the F134. So I would suspect it could pull a light, low profile trailer at 45 and not be overworking the engine.

 

My previous comment about 134 with overdrive was meant to imply using the OD for it’s overdrive function only.
For the most part an F134 will not be able to use an overdrive gear due to pulling extra trailer weight.
But for use as a gear splitter it excels and certainly should be used as it is plenty strong and durable.
I’ve had zero break downs or other problems with genuine Warn units.
I bought a new Warn OD back in the early 80’s and put well over 80 K miles on it before I disassembled and rebuilt that Jeep for its third life.
The new unit could have easily lasted 100 K total miles before the bearings needed to be replaced.
Unless running a Dana 20 TC, I will never be without a genuine Warn overdrive.
This holds especially true for the 134 powered Jeeps because gear splitting is so important.

 

As mentioed above, I don't think the limits are with the overdrive, but rather the rest of the Jeep.
-Donny