How difficult is replacing a C5 radiator? Told in the past that you have to remove the front nose of the car to access it. Indication is that it's an expensive repair!
Anyone have good/bad luck with radiator stop-leak additives to the coolant system? Any negative issues using stop-leak additives?

 

don't like stop leak and you do not have to remove the bumper, not really a bad job !!!

 

I just swapped out my original radiator and installed a Dewitt’s aluminum radiator and fan kit last winter. You don’t need to remove the front fascia unless you need to replace the lower radiator cage if it is damaged. You can access it from the top to perform most of the work but you will also need to raise the front up to gain access to the lower mounts and to drain the coolant.

There are a few good “how to” videos on You-Tube that walk you through the process. If you do replace it, it's a good time to swap out the belts, hoses, water pump, stat, balancer, etc. if you need to because you will have a lot more room to perform the work.

 

The hardest part when I swapped out my radiator for a DeWitt’s was the connectors to the fans that were located on the bottom of the shroud. Transmission lines if you have an automatic as well. After that it was pretty straightforward. Depending on the miles on the vehicle you may want to swap out the hoses, belts, expansion tank, thermostat and water pump while you have everything apart.

 

The easiest access to the cooling fan electrical connectors is to remove the four bolts holding the stabilizer or sway bar to the cradle and swinging the sway bar down out f the way.

The fan shroud and fans come out the top, as does the radiator.

Have a sheet of cardboard to temporarily tape to the new radiator rear face until after the fan shroud and fans are back down but not hooked to the radiator- to keep from damaging the new radiator fins.

I used SS worm gear clamps to replace all original clamps which are a pain to work with. The lower radiator hose connection at the radiator is very tight. I cut the original hose to get the radiator out. Be sure to coat the lower radiator outlet and the new hose with coolant to make it easier to get on.

THINK about new clamp orientation so you can get to them for re tightening.

Be SURE to use the Factory Service Manual procedure to remove air from the heads when you refill the system.

I put a DeWitts in in 2013, so I may have forgotten something. It took me 6 hours, start to running car.

 

I urge you to avoid leak radiator stop leak. Either a new OEM radiator, or choose from a handful of double row aluminum radiator manufacturers.

Here’s a list of all the coolant parts, aside from the radiator itself, and where to buy them. Frankly, I prefer the factory constant pressure clamps (included in the table); just need the proper pliers. They’re available on Amazon, and not expensive.

 

Youtube will be your friend. It's probably about a 2-3hr job if this is your first go around. Raise front end, drain coolant, remove intake, remove radiator/fan shroud, remove coolant upper/lower radiator hose, remove 2 upper remaining small coolant lines, [you'll have 2 additional lines if you have an automatic], "unhook" radiator fans, and then wiggle out the radiator. Just keep an eye out for the hardline that's "hooked" on the low passengers side of the radiator, that's the only "snag" I ran into when changing my radiator. Also swap in a new drain petcock, the stock one is a bit of a pain, getting one that has a tab makes life a lot easier. It's kind of nice to have a 2nd pair of hands when wiggling out the radiator.

 

What intake are you referencing?

 

Just thought I'd throw this out there. The factory constant pressure clamps are great-Until they get old, or too hot, or whatever. I developed a coolant leak by the water pump, one heater hose, specifically. Only leaked at high rpm, so hard to find initially. I replaced everything with real hose clamps, or as some call them, band clamps. No more leaks.......

 

I have the originals now 18 years old, no leaks. They don’t rust or break. The factory uses them because they stay tight in a wide range of temperatures and are very durable. I wouldn’t reuse 20 year old clamps, though, no matter their style or condition. Fortunately, we can still get the original clamps.

 

I have an aftermarket intake, so I just removed the entire intake. Not sure (if you have a stock intake) if you can get away with just removing the air intake tube and leaving the filter housing in place.

 

So, you’re referencing the air filter assembly and bridge, not the intake manifold?

That would make sense, just wanted to be sure that’s what you meant…

 

It is not hard if you are mechanically inclined and do other routine work on the car/have replaced a radiator before. The nose stays on as stated above. If you have an automatic you need a special tool to release the lines and be sure to order the correct radiator. I just did mine this summer. The tools come in a multi pack kit.If you can't find any and you need them let me know.

You may run into some foam insulation that seals air gaps coming off, but that is easily reattached with trim adhesive. Once it's coming apart you will see what I mean.

 

I did mine back in May - reading this thread brings back a lot of "fun" memories or bad dreams if you will, because at the same time I also installed the Improved Racing oil cooler kit, the '04-05 LS6 valve pan with the updated PVC hose setup and the Elite Engineering catch can, the TPIS 90mm LS6 intake with the 90mm throttle body, installed a 4-corner steam tube setup, etc... Hey if your going to tear it apart, do as much as possible. I should have done a few other things while I was in here, but that's another story.

Anyways changing the radiator is not really an easy one man job, even for those with a fair share of mechanical experience. As noted above, if you are doing just the radiator you do not need to remove the bumper facia, nor the hood. I did it by myself with the car on my QuickJack, but somehow you need to be top and bottom as well as left and right all at the same time. That's why having the help of a friend would be invaluable. Installing the HD all aluminum fabricated radiator vs. a stock replacement unit just complicates matters. Yes most definitely need / should cover the new radiator and the a/c condenser with cardboard to protect the fins. Getting the hooks and tabs lined up with the a/c condenser on the front and the factory cooling fan shroud on the back, all at the same time is a great generator of all kinds of fun words, so make sure the "womenfolk and young'uns" are not within ear shot.. Do not forget to reinstall the two lower rubber mounts/isolators either, they like to repeatedly pop off and fall to the ground, painter's tape can help. There is no extra room in there with the thicker radiator! Hoses, harnesses, hard lines, larger sway bar, then add some -10 AN oil cooler lines to the mix, etc... just not fun. The thicker radiator does fits in there and lines up, except in my case for the factory fan shroud tab driver's top under the radiator hose. It needed to be trimmed off and secured with a nylon tie strap. And yes its amazing how much better the thicker HD radiator (along with 1 more gallon of fluid capacity) keeps the coolant temperature under control all the times.

Also as noted above the factory side sealing foam on sides of the shroud is most likely shot at best or even missing. I cleaned the surface and used some 1"x1" neoprene adhesive backed foam tape to reseal the shroud to the a/c condenser.

https://cleverbrand.com/products/1-w...31685661163572

BTW, the radiator I pulled out was the factory original +23 year old unit that had +81K miles on it. It was not leaking. I only replaced it for track duty.

 

I truly believe the factory uses them on the line because they are fast, much faster than worm drive conventional hose clamps. I like the factory clamps. But once I got a leak from 1, the rest can't be far behind. So I changed them all. It may have to do with the hundreds and hundreds of heat cycles. Not really sure, because if they get hot enough to lose their tension, clamps would be the least of my worries!! I'm thinking it could be my own fault, because I never bought the correct special tool pliers, so I got by with channelock pliers, instead. They've been on 3 different engines now, and I'm reasonably sure I probably squeezed them a bit too tight a few times. Don't know for sure. What I do know for sure is you need the right tool for any given job, and I didn't have it for these, due to nothing more than being stubborn!!

 

Well, maybe cheap, too!!!

 

I haven't seen any follow up posts from you. If you have, and I missed them, I apologize. Anyway, IDK why youre changing the radiator. If its just to replace a leaky one, I'd NEVER go through the labor to just reinstall a new stocker. I'd go with a DeWitts. Just throwing this out there.......

 

I put in a DeWitts with trans and engine oil coolers in September 2013, also Improved Racing oil lines and Oil thermostat. Nine years,19 track days, 35,000 miles later I am very happy with the DeWitts and the SS worm drive clamps that went on at the time.

 

The stock one is cheap, available everywhere and easy to replace. You don't need to take off the whole nose of the car - just the radiator mounts and fans. It's actually easier than it looks. Good time to replace hoses and water pump. Friends don't let friends use stop leak.

 

Moved to C5 Tech. And good luck with the radiator replacement.