I have a 2010 Suburban 1500 LT with the 5.3L engine and 3.08 axle with 4wd (only 4Hi, no 4Lo). I recently bought a travel trailer.


I have already added a tranny cooler and brake controller so those are taken care off. So now the only difference between mine and one with the tow package is the axle.
I would like to upgrade the axle so it'll have more power for towing the long hills here in Colorado. I know for that year, GM puts in either the 3.08 or 3.42 axle depending on the tow package. If I do the upgrade the axle, I know I can go to 3.42 but wonder if I can put a Silverado's 3.73 axle in my Suburban.


I think since it's 4wd, I'll need to change both front and rear. Please correct me if I'm wrong.


Also would like to know from those who have done this, what's the ball park cost to pay someone to do this, and how difficult it is to DIY. My mechanical ability is somewhat limited. I can change brake pads and rotors and replace spark plugs. Never attempted anything more ambitious that those. Also where do I find the axles to buy? Junkyards? Online sources?

 

Don't buy a junkyard axle for your suburban. You'll be better off having a shop do the work with new parts. I suspect that it will impact the 4x4 front axle as well. I had my rear axles, differential, rebuilt a couple of months ago. It was spendy. I tow a 27 foot travel trailer with my burb. It's no racehorse pulling 6000+ pounds. But, it gets the job done. If I used it a lot more I would be looking for a 2500 Burb. But, for 3 or 4 times a year it's fine. If it involved redoing the front driveline I would pass on that expenditure. Seems like good money after bad. They don't make enough big, hefty SUVs for pulling travel trailers. Although, apparently Fords new Expedition XL is going to be a hoss.

 

First of all, how heavy is the trailer?
How much towing are you planning to do? Changing your axle ratios is going to be quite an expense for a marginal increase in performance.

I doubt it. It's still a half-ton platform, and regardless of the "trailer towing rating," the limiting factors will be payload and rear axle weight rating. I'll take my 9 year-old 3/4-ton Burb over any new half-ton SUV.

 

The trailer's dry weight is 4400 lbs and max weight is 5000 lbs. I'll be hauling four people, plus 4 kayaks on the roof rack maybe 5 to 6 times a year on trips anywhere from 60 miles to 900 miles from here. Will be going over some passes such as Independence Pass, Monarch Pass, etc. We bought the trailer in Omaha, NE and towed it back to Colorado climbing gradually all the way here and I noticed the SUV feels much "peppier" at 3000 to 3300 rpm but it's hard to find a cruising speed that's gets us that range. I haven't towed it full loaded up any passes yet. but just want to see if an axle upgrade even makes any sense financial wise.

 

Sounds like you're going to be at or over your payload and/or rear axle weight rating.

A half-ton Burb has a payload rating of about 1500 lbs. A 5000-lb trailer is going to put about 650 lbs of tongue weight on your truck. Add 50 for the weight of the hitch, then add the weight of 4 people and 4 kayaks, and I'm positive that will put you over 1500 lbs. Never mind the 4200-lb rear axle rating. I'm sure you'll be exceeding that, too.

The high altitude is going to take away 20% or more of your engine power. It's going to suck driving in the mountains, and changing your axle ratios won't fix that. On the plus side, you have a six-speed transmission, which will help.

Embrace the suck, and save your money.

I pulled a 7,000-lb trailer over Powder River Pass (9600 ft) with my '01 half-ton (4.10 and a four speed). The best she could do on the final ascent was 25 mph in first gear.

I dragged that same trailer through the Eisenhower tunnel (11,000 ft) and the best my 3/4-ton Burb could do was 40 mph in second gear at 4000 RPM.

On long tows, you're going to want to keep an eye on the rear axle temperature, especially during the summer. You should invest in an aftermarket diff cover with the cooling fins, to help dissipate heat. The '01 Burb is on rear end number four. It broke twice while on long trips while towing heavy.

 

On our first big trip (Memorial weekend), I'll have the combination weighed at a station to find out the overall weight and each axle's weight.


Dumb question: how do I check rear axle temperature? I don't recall that as one of the sensor readings on my cockpit display. Also when the rear end breaks, which part(s) break and what happens? Is it pretty much stranded and have to be towed? I don't know anyone who's ever experienced it so I have no clue.

 

Infrared thermometer that you can buy for $10?

I didn't have that - at every stop I crawled under the truck and felt the rear axle with my hand. If I could touch it, it wasn't too hot.

We were driving across SD on I-90 in the middle of summer. Axle overheated, cooked off all the axle fluid, and started making a godawful grinding noise. Was able to limp off the highway to a supermarket, called AAA for a flatbed and truck for the trailer. Spent 4 days in Mitchell, SD while a rear end was trucked in from Minneapolis. $2200 later we were back on the road. After that, for the rest of the trip, we did a lot of driving at night, when it was cooler.

Another time, I spun the pinion bearing, which again crippled the truck, necessitating a flatbed and second truck to tow the trailer.

Safety tip: Get AAA Plus RV road service membership. It's like $120 a year, but it'll pay for itself and then some if you ever need it. Even covers hotel, food and rental car in case of a breakdown.

The rear end is definitely the weak point of the half-ton trucks, IMHO. That's why I upgraded to the 2500. The rear axle in my Burb is rated by American Axle to 10,000 lbs in other applications. Plus everything else is heavier duty as well - engine, transmission, brakes, frame, suspension, tires, etc.

 

Thanks for the information. Will definitely keep an eye (hand) on that rear axle. We have a couple summer trips coming up. The only in July is the furthest about 6 hours away. All at a fairly high elevation but still gets hot around here. Will upgrade our AAA membership for sure.


We already have the 1500 burb so hoping not have to upgrade to another vehicle.


I double checked the spec of our trailer. The dry weight is 3822 lbs, while max weight is 5000 lbs.