02 Suburban 5.3 2wd...too slow now

marty79

marty79

Well-Known Member
Joined
Nov 24, 2013
Location
Newton, NC
need some direction here of what to do with current budget....(buying a nice "tow rig" truck out of question right now) soooo...
my 02 suburban 2wd 5.3 340K 3.73 rear, runs great, not a peep since we bought it with 281 little over year ago!
Tows great up till now...This darn Mountaineer on Tons apparently weighs WAY more than I thought, way more than my other buggy I had (5800 on last buggy).
Towing to the "get together" was stupid slow....like daiuum, poor Rubi did not like even the slightest hills and 3rd gear sucked...2nd gear was pegged just to maintain them little inclines on the way to Uwharrie...
Option 1: Slap a Cam and tighter springs in it and tune it....supposively will add 80hp???? (leave everything else)
Option 2: Only Regear from 3.73 to 4.56??? (not sure 4.10 would be worth it??)
Option 3: Sell it (3K) and take that money and put down payment on used Excursion V10, maybe 2500 Truck if I could find at a local car lot for payments but don't really want to...
Option 4: Cam and tighter valve springs, Tune it, AND 4.11 or 4.56????
Really need to figure something out cause I ain't towing my rig anywhere until I do something...she too weak for my new rig
 
my other buggy at 5800lb this 5.3 towed it just fine everywhere, never struggled in 3rd gear. I'm not a fan of towing with pegging the rev limiter in 2nd gear just to maintain 45 up a slight incline like what you get on I-40 on the way to Uwharrie or the Gulches so screw that, I gotta do something lol
 
It looks heavy just from your pfp. Were those body on frame?

Did you see the for sale listing on that clean flat dump bead 7.3?

Not sure what your budget is and it ain't none of my business. But..... if you're looking at a 2nd gen or 3rd gen Cummins and have concerns about it if its a good buy or not; I know an extensive amount of information about the 5.9s of late 2nd gen to early 3rd gen vintage from nearly rebuilding my own 03 6MT.

marty79 said:
nice "tow rig" truck
Click to expand...
Translates to pure and proper function in my ears.
 
marty79 said:
I could find at a local car lot for payments but don't really want to...
Click to expand...

Payments on a used vehicle and buy here pay here lots are a perfect storm for outrageous and predatory interest rates, not mentioning bringing the vehicle up to speed on repairs and maintenance. Don't have experience but I wouldn't want to either. Used Diesel trucks can get expensive fast, which I can speak from experience on.....
 
A cam that makes 80 more HP is going to need more supporting mods, like a higher stall converter. Higher stall converter equals more heat and bye bye 4l60.

I'd gear it and put a big trans cooler on it, but it sounds like you already know you're at its limits.

If the suburban already has the little trans cooler up front, the tru cool 40k is almost a direct swap with this guy's kit Tru-Cool Max Trans Cooler 4739 & 47391 Install Kit - Brackets & Fittings & Hardware - PerformanceTrucks.net Forums

I just put one on my 2500 6.0 yukon xl.
20210906_160603.jpg
 
Also, supposedly some escalades in that era got a 4.10 geared, coil sprung, semi float 14 bolt that would be a direct bolt in. I thought about going that route in my 1500 before I found the 2500.
 
LBarr2002 said:
gear it and put a big trans cooler on it, but it sounds like you already know you're at its limits.
Click to expand...
4.10 or 4.56? I feel like 4.10 wouldn't be worth the work, and 4.56 I would think would drastically increase my towing ability?
 
marty79 said:
4.10 or 4.56? I feel like 4.10 wouldn't be worth the work, and 4.56 I would think would drastically increase my towing ability?
Click to expand...

The only way I'd do 4.10 is if it was the bolt in 14 bolt. If you go through the trouble of regearing, I'd go deeper.

What size tires are you running and what kind of trailer are you pulling?
 
LBarr2002 said:
The only way I'd do 4.10 is if it was the bolt in 14 bolt. If you go through the trouble of regearing, I'd go deeper.

What size tires are you running and what kind of trailer are you pulling?
Click to expand...
265s, 20ft trailer that weighs about 1950ish.
I'd regear the 10 bolt most likely
 
Are you sure it has 3.73 gears in it? Yukon XLs and Suburbans usually came with 4.10s. Open the glove box and look for the RPO code. You're looking for GT4 or GT5.

A cam swap is opening a can of worms. It's not JUST a cam and heavier valve springs. It usually winds up being the cam, springs, spring seats, valve stem seals, valve locks, push rods (stock ones do NOT like heavier valve springs), water pump, timing cover gasket, front seal...and since you're at 340k miles...I'd probably pony up for new lifters, which requires pulling the heads, and I'd absolutely replace the oil pump and timing set. The oil pump has to come off to replace the crank gear for the timing set and you know that timing chain has some stretch in it by now. With decent parts, you'll be 1200 bucks or more in to it.

@LBarr2002 brought up a good point about the torque converter. Depending on the cam size, it'd need a different stall. The last thing you want to do is go through a cam swap and then not let it perform to its full potential or not be able to let it idle, in gear, with your foot on the brakes.

Do not be scared of RPMs and downshifting with a stock setup. It'll do it all day long. Just ask @77GreenMachine. It's just the nature of towing with a gas motor.

What size tires are on the Suburban? They look to be larger than stock, which will hurt overall gearing as well. Go back to stock or 265/70-16 max.

Worst case, swap a 6.0 in it and put 4.10s in if it really has 3.73s, which I don't think it does. I'd start with just tuning it though. Then maybe long tube headers, exhaust, an intake, and 05+ Silverado/Sierra electric fans with an ECM controlled harness. That'll free up some power.

If you haven't lately, a tune up couldn't hurt. NGK or factory Delco plugs, good wires (MSD 8.5mm wires are pretty cheap), a fuel filter, and check to make sure it has full fuel pressure/the pressure regulator isn't leaking. A weak fuel pump will kill all your performance!
 
Last edited:
My vote is not a V10s Excursion. You have a 5.3 already; I say put the money in the motor and trans you already have.
 
Croatan_Kid said:
Are you sure it has 3.73 gears in it? Yukon XLs and Suburbans usually came with 4.10s. Open the glove box and look for the RPO code. You're looking for GT4 or GT5.
Click to expand...
Its definitely 3.73
I looked into cam swap and your right for the mileage its stupid to not pull motor and do everything.
Did a tune up and maintenance when bought it!
Running 265s
Sounds like regear to 4.56, electric fan upgrade and maybe a tune is most economical route
 
BigClay said:
My vote is not a V10s Excursion. You have a 5.3 already; I say put the money in the motor and trans you already have.
Click to expand...
Only mentioned those cause they're readily available lol and I know they pull anything and I like excursions since we love camping in our suburban
 
A tune would certainly give you more ho and torque but at 340k miles that may cause you more problems. Pull motor replace wear parts out back in
 
Time right now is not in my favor to pull motor on this with work flow so either I'm regearing or selling lol
 
marty79 said:
Only mentioned those cause they're readily available lol and I know they pull anything and I like excursions since we love camping in our suburban
Click to expand...
Those V10s are also known for puking spark plugs so you need to invest in helicoils
 
BigClay said:
Those V10s are also known for puking spark plugs so you need to invest in helicoils
Click to expand...
I know I've owned a few fords lol
 
Croatan_Kid said:
Worst case, swap a 6.0 in it and put 4.10s in if it really has 3.73s, which I don't think it does. I'd start with just tuning it though. Then maybe long tube headers, exhaust, an intake, and 05+ Silverado/Sierra electric fans with an ECM controlled harness. That'll free up some power.
Click to expand...

My 1500 yukon xl has 3.42s. I have a wrecked Denali sitting in the back yard with 6.0/3.73s I intended to swap into it until I found the 2500.
 
Interesting. The two I've messed with were both half tons with 4.10s.

I think a 2500 Suburban would be the ticket for him. 6.0, 4L80E, and 4.10s in a 14 bolt full floater. Hard to beat for a stock setup. Tune that and roll on.
 
Although, I did just find an 8.1 Suburban in Fredericksburg, VA for 5500 :D Now we're talking! I love FB marketplace.
 
Regearing will get you the most bang for your buck hands down. 4.56 gears would be the way to go. I've done that for quite a few 1/2 ton GM truck/SUV owners who tow similar weight.
Grab a Trutrac while you're in the rear diff. You probably have a G80 which is a ticking timebomb.
 
Jody Treadway said:
Regearing will get you the most bang for your buck hands down. 4.56 gears would be the way to go. I've done that for quite a few 1/2 ton GM truck/SUV owners who tow similar weight.
Grab a Trutrac while you're in the rear diff. You probably have a G80 which is a ticking timebomb.
Click to expand...
If I dont sell it that'll be way I go.
So you also agree 4.56 is the magic number
 
Back
Top