rear gear swap

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
I have recently changed from a v hull to a toon and while the toon is a good bit lighter (500 plus pounds) the wind signature of the toon is a lot greater , and i have chosen to drop the rear gear , I tow with a 97 S 10 with a 4 banger 5 speed, its towed my old west winds for many years with no problems but it comes with a 3.73 , and a drop to a 4.10 should help out a good bit and give me a bit more torque on the ramp
 

jeeperman

Lieutenant Commander
Joined
Aug 2, 2001
Messages
1,513
Re: rear gear swap

A fullsize toon towed by a 4 banger S10?

You need more than gear change.

You need to upgrade to a fullsize vehicle.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: rear gear swap

I towed my pontoon with an S-10 crew cab/3.73 gears and it did it just fine but a GMC Yukon came along with my name on it and the difference is dramatic -- especially the comfort level. However, the 4.3 V6 is a stump puller compared to the four banger. But -- there should be a bunch of entire rear axle assemblies in the bone yards so that swap would be simple and cheap (relatively) so it may be worth a try. If it doesn't pan out, THEN look for an alternative.
 

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
Re: rear gear swap

yes i have all ready found one and plan on having it put in very shortly, and a fyi , a 4 banger , auto trans is rated at 2000, a 4 banger manual 5 speed is rated at 3000, droping the rear gear brings it up to 3500 or so im told, iv pulled my old boat with a weight of 2000 for many years the toon is around 1400 with gas n gear
 

90stingray

Lieutenant Junior Grade
Joined
Oct 26, 2010
Messages
1,162
Re: rear gear swap

Just fyi... dropping gear ratios does not bring up the tow rating of the vehicle. But if you are at 1400 lbs then go for it... but dont forget the weight of the trailer too :)
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: rear gear swap

yes i have all ready found one and plan on having it put in very shortly, and a fyi , a 4 banger , auto trans is rated at 2000, a 4 banger manual 5 speed is rated at 3000, droping the rear gear brings it up to 3500 or so im told, iv pulled my old boat with a weight of 2000 for many years the toon is around 1400 with gas n gear

I believe you are correct with the 4.10 rear being rated 3500 lbs (from reading owners manuals for vehicles I considered buying to tow), but they might have added some other equipment, like stiffer springs or sway bars, and larger radiator too. Remember your RPM will jump a bit with the 4.10, so keep an eye on the tach until you're used to it. And you can have the dealer re-program the computer so the speedo is correct, otherwise it will be off by the % difference between 3.73 and 4.10 (about 10%). So with no change to the computer, when the speedo says 60, the vehicle will actually be going 54 (speedo is reading 10% high).
 

Mi duckdown

Commander
Joined
Apr 14, 2007
Messages
2,575
Re: rear gear swap

I don't think changing from 3.73 to a 4.10 is going to help you out on the ramp.
 

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
Re: rear gear swap

It may not, but its more of a change for the mountains i have to deal with, if you have ever ran I 64 across west virginia any help is a good thing , Im not expecting any huge change , it pulls good as is , but it should allow a bit better pull on the mountains here , or so im told by some friends in the S 10 forums who live in the area, if i was on flat lands i wouldnt bother to change it , and yea im sure it will drop fuel milage, it gets 30 now on the interstate, im expecting 20 to 25 ,. but thats just the price you pay , its one of those things ill give it a try and see what happens
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: rear gear swap

......., and yea im sure it will drop fuel milage, it gets 30 now on the interstate, im expecting 20 to 25 ,. but thats just the price you pay , its one of those things ill give it a try and see what happens

Well, I can tell you that changing the rear in the Firebird from 3.08 to 3.73 (a 23% change in gear ratio) only lost me about 1 MPG on my average MPG, and nothing on the highway MPG. People on forums told me to expect a 3-5% loss of economy, but it just didn't happen. I expect you will see very little, if any change in MPG (after you get over the first week of tire smoking burnouts) :D

And spend the bucks for the Eaton Trutrack all gear posi, it is worth the investment (and no clutches to burn out or wear or chatter). Also it would be a good idea to drain the gear lube from the trans and fill it up with a quality synthetic lube. Also use synthetic for the rear. Between the two, you will only be spending a few dollars more than traditional gear lube.

You might find this interesting: http://www.shareaproject.com/pages/projectTut,p,550,00.html
 

jigngrub

Fleet Admiral
Joined
Mar 19, 2011
Messages
8,155
Re: rear gear swap

This is how I tow my boat!

http://www.youtube.com/watch?v=inSFAL47xd8

I think your S10 with 4 cyl. and 410 rear end is waaaay overkill.:rolleyes:

You have way too much weight in the rear end and and your vehicle is too heavy, that boat will never be able to push the rear end around to the front during a quick stop or on a wet road.
 

jeeperman

Lieutenant Commander
Joined
Aug 2, 2001
Messages
1,513
Re: rear gear swap

You might actually get better MPG when towing with 4.10 gears versus 3.73 gears.
All depends where the "sweet spot" is for the vehicle and load.

I think going from 3.73 to 4.10 will be such a minor change, you will be wondering if the effort was really worth it.
 

H20Rat

Vice Admiral
Joined
Mar 8, 2009
Messages
5,204
Re: rear gear swap

Just fyi... dropping gear ratios does not bring up the tow rating of the vehicle. But if you are at 1400 lbs then go for it... but dont forget the weight of the trailer too :)

depends... what was the limiting factor for what it was rated at before? Without knowing that, it is POSSIBLE that power was the limiting factor, and in that case, yes, lower gear ratio will help.
 

boatnut74

Lieutenant Commander
Joined
Aug 29, 2010
Messages
1,835
Re: rear gear swap

IMO I would look for a different tow vehicle. 3.73 to 4.10 will give you very little if any noticable differnce. I switched from 3.55 to 4.56 in my F150 and didnt really notice much of a change. The final decision is up to you but thought I would throw in my .02 from my experience swapping gears.
 

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
Re: rear gear swap

well the parts came in today , and it will be changed out next wensday, and i will see , it may or not work , but i will find out
 

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
Re: rear gear swap

I got the rear gear changed a few days ago and put it through a brutal tow today. 375 miles of 6 to 11 % grades. and it worked fine and gave me the extra I as expecting , it made it a lot easer, and gave me a good bit more lower pull out on the ramp. in the past on this route I have gotten 14 mpg , and it looks like it droped off to 12 MPG, so well worth it, grins and monday Ill be out to my normal fishing spots , so I will have a better idea on performance , but yea I am very happy with the change
 
Last edited:

hrdwrkingacguy

Petty Officer 1st Class
Joined
Mar 9, 2010
Messages
368
Re: rear gear swap

I put a positrac and a 4.10's in my silverado and it was night and day better...Getting to the lake, and getting out of the water at the ramp was way less stress...:eek:
 
Top