newbie and confused

LarryJM wrote:

gmw photos wrote:

As for changing the ring and pinion in the trucks rear end, you do understand that an easier way to get the engine to rev higher, is to simply use a lower gear in the transmission ? The whole object of the game in going to a lower gear ratio in the final is to get the engine to rev higher up into it's powerband. Which is exactly what you do when you leave the trans, let's say in third, rather than in fourth. If I were in your shoes, I would choose and buy the trailer, and try towing with it before going to the expense of changing the final gears.

While that is true at cruising speed there is the acceleration factor and such things as torque multiplication where a higher rear end gear will help a lot in getting all that weight up to speed. A higher rear end gear will give you more "power" where the rubber meets the road as you accelerate up to your final cruising speed.

Like some others have posted personally if you are going to change the rear gears from your current 3.23 I would seriously consider skipping the 3.73 and go straight to the 4.10 if the costs are close to the same. Except for some the the newest diesels and some of the more modern trannys with 6 speeds, etc. the typical "TOWING" rear ends are in the 3.73 to 4.30 range.

Larry

Larry,
What you say is true. And if we want to get technical about it, to take it a little further, going to a lower ratio rear end also helps reduce the strain on the transmission, since "more" of the torque multiplication is taking place at the ring and pinion. In theory anyway, with a lower rear gear he could see cooler trans temps.
This is likely part of the reason Toyota has chosen 4.30 gears in the late Tundras. It makes life easier on the trans. Late GM trucks though have gone the other way, with higher rear gears, and choose to get the torque multiplication in the trans.
Having said all that, my point in suggesting to the OP he try it out first with the stock gears is because changing rear gears is fairly expensive, and depending on the trailer he chooses and what his towing expectations are, he may be satisfied with what he has. One needs to consider too what percentage of their annual driving with this vehicle is towing vs simple everyday use. For occasional weekend use, and a couple week vacation once a year as a tow vehicle, it may make more sense to just leave the rear end gears alone, and deal with somewhat slower acceleration while towing.
Going from his existing gear to a 4.10 or so is going effect his gas mileage some in daily non towing use as well.

Another thing for him to consider would be when it's time to replace tires on the truck, going to a tire with a slightly smaller rolling diameter has the same effect as lowering the gear ratio.

While I won't go so far to say these small block chevy V-8's are gutless, I will admit, both this engine and 5.3 like to rev. True small block design there, they are tuned so that you have to rev them. Do it.....won't hurt a thing, except maybe gas mileage.

I agree with Larry also that the change from 3.23 to 3.73 is not much of a change, so if going to the trouble to change them, I too would go to 4.10 or even 4.30. OP, there are charts and graphs online that will allow you to see what change of rpm you would see by changing the gearing. You might want to do a little homework on it.

ps. where is the hone-o-drive when we need it ? :)