Chevrolet Suburban 3500 Questions

[Geotrash]

The steering box is no longer for sale… because I bought it lol.

Turns out these things are near unobtainium… $1000+ from the dealer and $800+ from RockAuto. Likely will rebuild the one that failed and either keep it as a spare or list for sale.

Wow...hope it proves to be a legit good part. Something else for me to keep an eye on. I'll also keep an eye out on the junkyard network for a wrecked one I can grab the box from and rebuild it on the bench. Thanks for clueing me in to the issue.

 

[Bigburb3500]

Wow...hope it proves to be a legit good part. Something else for me to keep an eye on. I'll also keep an eye out on the junkyard network for a wrecked one I can grab the box from and rebuild it on the bench. Thanks for clueing me in to the issue.

There was one I found recently listed in a yard but the front was mangled. Not sure if this is a “common” failure but we have a dipstick for power steering fluid. Just check regularly. In the end… I will likely have a rebuilt one and we can split pricing on it. Just ship or drop off the core for rebuild hahaha

 

[Bigburb3500]

Ok. Steering gear box was replaced the other day. Just needs an alignment. Place cut me a deal on labor and only charged 3.5hr but book was 5 or 6hr. They said that was complete overkill. Will post pictures of the failed part later.

 

[Bigburb3500]

Havent gotten the pictures yet… been a little busy with life and all but did get the truck fixed and back on the road!

New issue I found is that my coolant level seems to be dropping… no white smoke out the tailpipe and only 85k so head gasket is an unlikely item. I also recently did an oil change (check dipstick too) and the oil looks like normal engine oil. I have topped it off and noted the mileage. Will keep an eye on it and poke around the engine bay for any leaks. I would assume a leak is more likely than head gasket or radiator failure at this point.

 

[Geotrash]

Havent gotten the pictures yet… been a little busy with life and all but did get the truck fixed and back on the road!

New issue I found is that my coolant level seems to be dropping… no white smoke out the tailpipe and only 85k so head gasket is an unlikely item. I also recently did an oil change (check dipstick too) and the oil looks like normal engine oil. I have topped it off and noted the mileage. Will keep an eye on it and poke around the engine bay for any leaks. I would assume a leak is more likely than head gasket or radiator failure at this point.

Now this is getting into the realm of stuff we ALL deal with eventually on the GM large SUV platform. You're right to not suspect the head gasket first. The things I would look at (in order):

1/ All coolant hose connection points. If any of the hoses have ever been removed, it's common for them to not reseal fully - especially if a worm drive hose clamp was used.

2/ The coolant tees by the firewall. They're easy to inspect for any coolant residue or leakage, and at 8 years old and approaching 100K miles, they are coming due within the next couple of years.

3/ The water pump shaft seal. Check for residue and leakage with an inspection mirror.

4/ The radiator end tanks. Sniff around when the engine is warm. If you smell that sweet evaporating coolant smell, you may have developed a hairline crack in one of the radiator end tanks. Look for coolant in the radiator support underneath it, and for residue on the end tanks themselves. These things are as much age-limited as they are mileage. 10 years and 150K seems to be the replacement point for it, but with the ride firmness these have, it could put more strain on the plastic coolant bits than normal.

5/ The heater lines extending back to the rear HVAC components. Check the compression fittings where the rubber lines meet the hard lines, and also the elbows that they connect to under the rear HVAC area.

6/ The 823 aluminum heads have had rare instances of cracking between the combustion chamber and the exhaust ports - especially on early model year castings, but since you're not seeing any evidence of either coolant in the oil, (or subtle white smoke that stays close to the ground coming from the exhaust?), I don't suspect this in your case.

 

[Bigburb3500]

Now this is getting into the realm of stuff we ALL deal with eventually on the GM large SUV platform. You're right to not suspect the head gasket first. The things I would look at (in order):

1/ All coolant hose connection points. If any of the hoses have ever been removed, it's common for them to not reseal fully - especially if a worm drive hose clamp was used.

2/ The coolant tees by the firewall. They're easy to inspect for any coolant residue or leakage, and at 8 years old and approaching 100K miles, they are coming due within the next couple of years.

3/ The water pump shaft seal. Check for residue and leakage with an inspection mirror.

4/ The radiator end tanks. Sniff around when the engine is warm. If you smell that sweet evaporating coolant smell, you may have developed a hairline crack in one of the radiator end tanks. Look for coolant in the radiator support underneath it, and for residue on the end tanks themselves. These things are as much age-limited as they are mileage. 10 years and 150K seems to be the replacement point for it, but with the ride firmness these have, it could put more strain on the plastic coolant bits than normal.

5/ The heater lines extending back to the rear HVAC components. Check the compression fittings where the rubber lines meet the hard lines, and also the elbows that they connect to under the rear HVAC area.

6/ The 823 aluminum heads have had rare instances of cracking between the combustion chamber and the exhaust ports - especially on early model year castings, but since you're not seeing any evidence of either coolant in the oil, (or subtle white smoke that stays close to the ground coming from the exhaust?), I don't suspect this in your case.

Thank you! Very familiar with the firewall T’s… did those on my 01 and were a bear!

Isn’t the L96 an iron block not aluminum?

 

[Geotrash]

Thank you! Very familiar with the firewall T’s… did those on my 01 and were a bear!

Isn’t the L96 an iron block not aluminum?

Yes, but the heads are aluminum. Same heads as the L92 & L94, btw.

 

[Bigburb3500]

Yes, but the heads are aluminum. Same heads as the L92 & L94, btw.

Ahhh. See, still learning something new every day!

 

[Bigburb3500]

Does anyone know if the Brembo big brake swap is superior to the 3500 brakes?

 

[Geotrash]

Does anyone know if the Brembo big brake swap is superior to the 3500 brakes?

Hmmm... I'm not aware of a Brembo big brake kit for the Suburban 3500. I know Wildwood makes one. Do you have a particular kit in mind? I would welcome the learning!

 

[Bigburb3500]

Hmmm... I'm not aware of a Brembo big brake kit for the Suburban 3500. I know Wildwood makes one. Do you have a particular kit in mind? I would welcome the learning!

Nothing in particular. I was actually wondering if anyone knew if the Brembo kit is better than the 1-ton brakes. I was lurking around some other forums for the Sierras/Silverados and there was no explicit conclusion I found. Wondering if anyone here had any thoughts.

 

[Geotrash]

Nothing in particular. I was actually wondering if anyone knew if the Brembo kit is better than the 1-ton brakes. I was lurking around some other forums for the Sierras/Silverados and there was no explicit conclusion I found. Wondering if anyone here had any thoughts.

Gotcha. AFAIK, the Brembo big brake kit others are using are only made for the 1/2-ton, 6-lug rigs. The only significant upgrade I know of for our 8-lug Suburban 3500's is the Wilwood, and they are pricey!

Wilwood Silverado 3500 TX6R Front Big Brake Kit with 15-Inch Slotted Rotors; Red Calipers 140-13873-R (11-19 Silverado 3500 HD)

FREE SHIPPING! High-Performance Braking System. The Wilwood TX6R Front Kit 15.00in Red is engineered for truck, SUV, and armored vehicle applications requiring

www.americantrucks.com

 

[Bigburb3500]

Gotcha. AFAIK, the Brembo big brake kit others are using are only made for the 1/2-ton, 6-lug rigs. The only significant upgrade I know of for our 8-lug Suburban 3500's is the Wilwood, and they are pricey!

Wilwood Silverado 3500 TX6R Front Big Brake Kit with 15-Inch Slotted Rotors; Red Calipers 140-13873-R (11-19 Silverado 3500 HD)

FREE SHIPPING! High-Performance Braking System. The Wilwood TX6R Front Kit 15.00in Red is engineered for truck, SUV, and armored vehicle applications requiring

www.americantrucks.com

Whew… $6k for front and rear… wow… would rather use that for a super charger…

Procharger is about $9k and then another $3k for install? Seems a better spend.

 

[89Suburban]

Now this is getting into the realm of stuff we ALL deal with eventually on the GM large SUV platform. You're right to not suspect the head gasket first. The things I would look at (in order):

1/ All coolant hose connection points. If any of the hoses have ever been removed, it's common for them to not reseal fully - especially if a worm drive hose clamp was used.

2/ The coolant tees by the firewall. They're easy to inspect for any coolant residue or leakage, and at 8 years old and approaching 100K miles, they are coming due within the next couple of years.

3/ The water pump shaft seal. Check for residue and leakage with an inspection mirror.

4/ The radiator end tanks. Sniff around when the engine is warm. If you smell that sweet evaporating coolant smell, you may have developed a hairline crack in one of the radiator end tanks. Look for coolant in the radiator support underneath it, and for residue on the end tanks themselves. These things are as much age-limited as they are mileage. 10 years and 150K seems to be the replacement point for it, but with the ride firmness these have, it could put more strain on the plastic coolant bits than normal.

5/ The heater lines extending back to the rear HVAC components. Check the compression fittings where the rubber lines meet the hard lines, and also the elbows that they connect to under the rear HVAC area.

6/ The 823 aluminum heads have had rare instances of cracking between the combustion chamber and the exhaust ports - especially on early model year castings, but since you're not seeing any evidence of either coolant in the oil, (or subtle white smoke that stays close to the ground coming from the exhaust?), I don't suspect this in your case.

I particularly support #4 in my experience.