Upgrade to 4.10 gears

[dcarver1987]

Pulling with a 03 suburban 1500 5.3 with 3.73 gears. Jumping up to the bigger trailer I've noticed more of a struggle to stay in OD. Currently on any kind of an inclince it drops into 3rd and sometimes second. At 62 mph and in OD I'm turning about 1900rpm. I'm guessing 4.10s would put me somewhere around 22-2300 rpm. Would this increase in RPM be noticeable? Also would this affect my towing mpg for the better considering I'd stay in OD a little longer? BTW I do tow in tow/haul mode. apparently the GM tow/haul mode just firms up shifts and holds passing gear a little longer.

[acadianbob]

I don't think it would be worth your expense to change gearing. There isn't a lot of torque in a normally aspirated V8 at that RPM range.

[Cajun Po-Boy]

Originally Posted by acadianbob

I don't think it would be worth your expense to change gearing. There isn't a lot of torque in a normally aspirated V8 at that RPM range.

X2...plus factor in the additional fuel cost, towing & non towing with 4.10's...IMO, live with what you have until you upgrade to a stronger/more economical towing TV.

[raspivey]

I thought about it last year. It was going to run me over $1000 for a gear swap. I think when I calculated the fuel savings when towing vs non towing and took into consideration how often I would be towing with it (I think I used an average 2mpg gain towing and 1mpg loss when not just for an idea) it would have taken me almost five years to break even with the cost. Wasn't worth it. I just take the hit when I tow and generally drive without OD to keep it around 2200 rpm.

[vinmaker]

What is the typical expense to do that? Is it a transmission gear change or a rear end gear change? I remember the kids in High school ( we called them gear heads because they always talked gear #. lol) would pull off the rear end case and change out gears to 4.10 gears on the mustangs or camaro's. Am I thinking about something else?

[raspivey]

It's a rear end swap. Not hard to do and the parts don't cost but a couple of hundred. I'm half afraid to do it myself due to having to have the clearances just right so I'd rather pay to have this one done. Just paranoid about having it come apart on me at the worst possible time. I think I was quoted around $1200. If I were still in high school I wouldn't worry so much...just have to get a ride if it broke. I've just never done one and, if I screw up, just don't have the time or patience any more.

[thebrakeman]

If your transmission is hunting, pull it down to 3rd and leave it there until you get to a stretch of flat ground. Who wants to take a mpg hit for the 95% of driving you do without the trailer?

[OldCoot]

According to my Chevy manual, you shouldn't be trying to pull in OD. If mine is in Tow/Haul mode, it won't shift into OD until over 65mph and I don't pull that fast due to ST tires.

[dcarver1987]

Well next August we will be full timing for 1yr for my clinical rotation so my suburban will become a 100% tow vehicle and then upon graduation will stay that way as I will be able to afford another car that will become my DD.
As far as my tow/haul mode, I'm not sure why but it always shifts into OD whenever tow/haul is engaged no matter what speed.
If I was able to spend $3-5k I'd sell my suburban and by a diesel but no a smart move financially since the upgrade to a new TT.
I've been given an allowance from the wife of $800 to improve the towing capability of the suburban so I thought 4.10s would be the best bet. It's a 2wd so that does keep costs down a little.
Anyway I appreciate the input. Not dead set on gears. Just curious if it would even be an improvement over the 3.73s

[raspivey]

I don't think you'll see all that much of a difference. Get a quote on it anyway. I don't think you'll be inside that $800 unless you do it yourself.

[offroad]

A number of years ago I had a 2001 Chevy with the 6.0L gas engine and 3.73's.
We traded up to a 30' 5th wheel and had a trip to Colorado planned that summer. After a few local trips and unhappy with its performance, I paid to have 4.10's put in.

The truck was still under powered IMO, and when my FIL offered to sell me his 97 Dodge with CTD I bought it. I put on some mild mods and I'm still driving it (only 113k miles), and its never been under powered in any terrain.

I wasted money on the 4.10 swap on my truck, and I'm betting you'll feel the same if you do it. I'd get a different truck.

[OldCoot]

I believe I would spend the $ to find out why it shifts into OD at any speed when the T/H mode is engaged. Something is definitely amiss.

[Iwannacamp]

My truck(diesel) has 4:10 gears. If I keep about 2000 RPM's the fuel mileage is ALOT better.

I guess about every town has a 4x4 shop. That's who I would get to change the gears. They do it a lot and prolly cheaper. Some GM's you have to change part of the carrier to change to some ratios. They can tell you.

I really don't see a lot of difference in performance except at take off.


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[Wa11y757]

Don't forget to add the cost for the front too if it's 4x4.

[cpaulsen]

I went from 3:73 to 4:30.......made a world of difference. Got better mileage towing and lost a little empty. Use the truck almost 100% just towing my 5ver so the mileage empty is not even considered. I hold OD longer and not even go into 2nd gear any longer. Since we are full time.....it worked for us.

[AquaMan]

Originally Posted by OldCoot

I believe I would spend the $ to find out why it shifts into OD at any speed when the T/H mode is engaged. Something is definitely amiss.

The tow/haul button does not lock out OD, it moves the shifts points depending on speed and load. You never hit OD because you drive like an OLD COOT.

One thing I haven't seen is (maybe I missed it), but what kind of trailer and/or weight is the OP pulling. This will make a difference on whether a gear change would be worth it.

[OldCoot]

Originally Posted by AquaMan

The tow/haul button does not lock out OD, it moves the shifts points depending on speed and load. You never hit OD because you drive like an OLD COOT.

One thing I haven't seen is (maybe I missed it), but what kind of trailer and/or weight is the OP pulling. This will make a difference on whether a gear change would be worth it.

Like I said, AquaMan, I very rarely tow over 65 and it doesn't get into OD.
65 is max on the st tires.

[Cajun Po-Boy]

Originally Posted by dcarver1987

Pulling with a 03 suburban 1500 5.3 with 3.73 gears. Jumping up to the bigger trailer I've noticed more of a struggle to stay in OD. Currently on any kind of an inclince it drops into 3rd and sometimes second. At 62 mph and in OD I'm turning about 1900rpm. I'm guessing 4.10s would put me somewhere around 22-2300 rpm. Would this increase in RPM be noticeable? Also would this affect my towing mpg for the better considering I'd stay in OD a little longer? BTW I do tow in tow/haul mode. apparently the GM tow/haul mode just firms up shifts and holds passing gear a little longer.

Gears downshifting during any incline while towing your TT with any gas engine is normal...plus, heavier the rv, harder the engine/tranny has to work to keep speed...also, your 5.3 performance specs in a 2003 is a lot different than 5.3's of newer trucks with a tow package setup...it is what it is

[dcarver1987]

Originally Posted by AquaMan

One thing I haven't seen is (maybe I missed it), but what kind of trailer and/or weight is the OP pulling. This will make a difference on whether a gear change would be worth it.

TT is a 2010 surveyor sport 295 dry weight 4815. Haven't hit the scales but currently we travel very very light so I'd bet on not being over 6k

[AquaMan]

If you are/will be full timing in it, I would think you are at your top end of GVWR for the camper. Now how far do you plan on traveling overall? How long do you plan on traveling between spots? And how long do you plan to stay in one spot? This will help give us an idea on actual need vs want.


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