Suburban 5.7 owners

[bwaysteve]

I have a 91 chevy 1500 truck that I plan to tow my 65 Ambie 4040lbs.for the time being. It's what I have currently.I have been told I should get an equalizing hitch and anti sway.
I am interested in a 99 year Suburban.Other than the closed in vehicle am I in the same ballpark of specs with the 1500 Suburban? both are 5.7s.
Am I buying anything going to the Suburban 1500 over the truck?Does 4x4 make any dif in ratings?
Would love a 3/4,but they got real pricey all of a sudden(like double or more the 1500.)

[68 TWind]

Be aware of of couple of issues with 99 Chevy's. First is they are notorious for bad front brakes and warping rotors. I have 99 Tahoe and I am on the 3rd or 4th set of front rotors. This time I bought the super premium ones from NAPA and their best pads and so far have been happy. If you feel any vibration upon braking, you will have to fix it. Turning the rotors is a short term fix. Second issue is the transmission, 4L60E. I had to do a rebuilt at 65K and that was all miles with no towing. Lot's on the internet about problems with that tranny. The good news is that if it has been rebuilt in the last few years the aftermarket tranny parts manufacturers have beefed up the problem parts.

[Jammer]

The Suburbans are basically the same as the truck give or take the added weight and cost.

Generally 4x4 will lower the towing ratings due to the weight of the transfer case and front axle and diminish the steering performance somewhat. But then it won't leave you stranded if you park your trailer in the grass and have to leave on a dewy morning. Maybe not a problem in Texas.

There are 2500s out there but yes they usually are more expensive.

[bobfowler]

I have a 5.7L '99 K1500 'Burb. It tows my 4000+ trailer with no problems at all. My tranny is the 4L60E - thus far no problems and I'm at 136K miles. YMMV.

[bwaysteve]

So basically I could go with the 1500 rather than the 2500 with the 454 and still be good?
I just don't want to be slapped all over the highway in a truck too light.I could go either way at this point but looking for best options between milage and stability.

[Jammer]

As 68Twind notes the 4L60e transmission is really not suitable for what you're doing.

The 2500 Suburbans of that era have the much heavier duty 4L80e transmission.

[68 TWind]

Bob, your are one of the lucky ones on the tranny issue. The problem with that tranny was a whole series of those had valve body problems. The material that the valve body was made of was too soft and that cause premature wear in the bores where the pistons move. After a short while the shift pistons would start to stick due to the out of round bore. There was a fix that involve reaming the valve body and installing hardened sleeves. I did this to mine, a pain I might add cause I bought the reamer and did it myself. This gave me another 25K, but after that the reverse gear failed (the other big problem). That was over my skill level so I took it to a shop. The guy had 3 4L60e's on the bench when I took my Tahoe in. Said that and the tranny out of the Ford taurus paid his grocery bill.. Glad you are still running. Maybe yours was a later series of production.

[bobfowler]

Originally Posted by 68 TWind

Bob, your are one of the lucky ones on the tranny issue. The problem with that tranny was a whole series of those had valve body problems. The material that the valve body was made of was too soft and that cause premature wear in the bores where the pistons move. After a short while the shift pistons would start to stick due to the out of round bore. There was a fix that involve reaming the valve body and installing hardened sleeves. I did this to mine, a pain I might add cause I bought the reamer and did it myself. This gave me another 25K, but after that the reverse gear failed (the other big problem). That was over my skill level so I took it to a shop. The guy had 3 4L60e's on the bench when I took my Tahoe in. Said that and the tranny out of the Ford taurus paid his grocery bill.. Glad you are still running. Maybe yours was a later series of production.

According to my VIN, my truck was made in August of '99, so it's one of the last '99s made. I also bought it with 65K miles on it - the PO may have had it rebuilt.

[flyfishsim]

Not a 99, but I have a 97 GMC Suburban with 377,000 miles. Replaced the transmission at 60,000, been running great ever since.

[rangebowdrie]

One of the best things, in the '96>'99 years, is the engines had the Vortec heads, along with a more direct fuel injection system, instead of the old throttle body unit,also they started using roller camshafts, those changes alone added ~55hp. Also, better mileage.

[bwaysteve]

Does anyone know what year they went to the L480e trans?

[lsuarch1]

Our 1991 Suburban 2500 has 4L80E transmission. I have been told that was the first year. We bought it about a year ago with just over 100,000 miles on it. We had some shifting issues & replaced the throttle position sensor & it runs great. My understanding is that there were faulty electronic parts on the transmission - not sure if previous owners had those fixed. We replace the i/o sensors & wiring cable when the shifting problems first started.

[Pat Conway]

We had a 99 1500 Suburban we bought used with 67,000 miles on it. It was a beautiful and comfortable vehicle, but almost immediately we had to contend with a load noise coming from the differential that couldn't be repaired/relieved with readjustments or synthetic gear oil. At 87000 miles the A/C compressor gave up. At 98,000 the fuel pump quit when climbing the grade west of Chattanooga on the interstate with semi trucks barreling up on us before I could get off on the shoulder. Along with the fuel pump came catalytic converter replacement. We pulled a 25ft A/S which was heavier than yours, the Suburban lacking in hill climbing power and dangerously slow when merging, especially an uphill on-ramp. I towed mainly in D-3 except when bogged down on hills, then in 2nd gear and maxing out at 35mph many times, with everything on the road passing me. Possibly the newer Suburban 1500 with the tow-haul feature would do better? Some have described the 1500 Suburban as more aligned with taking the family boat to the lake nearby about twice a year. As far as being happy with it for towing your trailer all over the country I think you would be happier with a more powerful motor and other strengths of a 2500. We kept our Suburban about $3000 too long before finally springing for a 2500 Duramax. The difference has been like night and day in overall towability. My two cents, Pat.

[rangebowdrie]

Including the Sub, that I have now, ('97 2500), I've had several 350s, the key to towing with them is 4.10 gears,,,,and keep the revs up. No,, they will not pull like a big block, but they do ok with the lighter weight trailers. I'll say again,,,4.10 gears.

[Jammer]

Originally Posted by bwaysteve

Does anyone know what year they went to the L480e trans?

It's not year, it's model. The 1500s got the 4L60e, and the 2500s got the 4L80e.

[bwaysteve]

Originally Posted by Jammer

It's not year, it's model. The 1500s got the 4L60e, and the 2500s got the 4L80e.

That's what I thought.From all the input it sounds like the best way to go is for a Burb is a 2500 with the big block from 91 on.Thanks

[howco]

I have two Burbans. Both 1500's w 5.7 motors.
One is an 89 4x4 and the other is a 2004 2wd.
I tow a 1970 27' Overlander with the 89 4x4.
I like the 89 because the 4x4 is more solid on the freeway and I like the option of 'not' getting stuck.
The 89 is fine on flat ground at 60-65 mph, over the mountain passes, I just put on the 4 way blinkers and cruise at about 35 mph, with the semi trucks.
No problem....

[bwaysteve]

Originally Posted by howco

I have two Burbans. Both 1500's w 5.7 motors.
One is an 89 4x4 and the other is a 2004 2wd.
I tow a 1970 27' Overlander with the 89 4x4.
I like the 89 because the 4x4 is more solid on the freeway and I like the option of 'not' getting stuck.
The 89 is fine on flat ground at 60-65 mph, over the mountain passes, I just put on the 4 way blinkers and cruise at about 35 mph, with the semi trucks.
No problem....

Howco,I am probably at about the same weight or close to your OverlanderDo you know final gear ratio on the 4x4?What MPG is average on the 89 4x4 traveling non mountainous terrain?My 1500 has the 5.7 and is a great engine.

[overlander64]

Originally Posted by bwaysteve

So basically I could go with the 1500 rather than the 2500 with the 454 and still be good?
I just don't want to be slapped all over the highway in a truck too light.I could go either way at this point but looking for best options between milage and stability.

Your intended use can make a huge difference in your satisfaction level with the less powerful C/K 1500 5.7 Liter compared to a C/K 2500 7.4 Liter Suburban. I traded my 1995 K 1500 Chevrolet Z71 with 5.7 Liter on my K 2500 Suburban in April 1998 (1999 model year Suburban). The 5.7 liter was grossly underpowered for my travels in the Rocky Mountains with my '64 Overlander (4,440 pounds dry/5,900 pounds loaded for vacation), and was my sole reason for trading the K1500 truck in 1998 as it only had 48,000 miles.

The 1999 K2500 Suburban is still in my garage and serves as my primary long-distance tow vehicle with 199,990 miles on the odometer. The transmission is original and has received only regular transmission service at 30,000 miles intervals. The motor has required only a timing gear and chain set at 180,000 +/- miles, and oil pan and main bearing seals at 185,000 +/-miles. The only issue I have with my K2500 Suburban is its electronic transfer case - - the circuit board that controls all operations of the transfer case tends to fail every 15,000 miles and at $750 for the part and the labor to install it has made the four-wheel-drive an expensive option that I will not purchase on my next tow vehicle - - a locking rear differential is just as effective but less costly to maintain. Currently, I am waiting for my mechanic to make a cost comparison to complete the transfer case repair again compared to the cost of converting back to 2WD.

Good luck with your investigation!

Kevin

P.S.: The Suburban actually averages close to 2 MPG better when towing than the less powerful K1500 did, and solo the difference is only readily apparent in town (the Suburban looses 3 MPG to the 5.7 Liter 1500).

-- K1500 -- solo 18 MPG Highway -- 9 MPG Towing -- 3.73 differential gearing

-- K2500 -- solo 17 MPG Highway -- 12 MPG Towing -- 4.10 differential gearing

[bwaysteve]

Kevin,
Great info!!! This really helps compare the two.The 2500 seems to be a great truck,but everyone has problems with something different on each vehicle so it's not just one one bad flaw inherent to all.