hotwheels57

On the backside (closest to motor) of the **upper radiator support (radiator cover on top w/ "caution fan"), there are three "fingers" for lack of a better word. I believe their purpose is to secure the upper edge of the electric fan shroud.

Could someone please check and confirm (or take a close up image) the correct positioning of those three fingers in relationship to the fan shroud? It would probably be best on a C5/Z06 which has never had the top cover off.

Right now, only the middle "finger" is holding the shroud on mine. The two outboard narrower fingers are fitted towards the inside of the shroud. I'm not certain if they too should be on the outside. Forcing them to the outside edge seems to put to much tension on the shroud.

Thanks.

**#1 in this schematic...

CHJ In Virginia

All three fingers should be over the top of the plastic fan shroud. If they are too tight, check radiator, fan and sealing foam strip alignment.

hotwheels57

Thanks.

KGoodwin

When I attempt to have all three upper radiator support tabs over the top of fan shroud, the two outboard corners pop right out. The upper radiator support bolts are tightened to 8 Nm as per the shop manual but the upper radiator support tabs are being forced up and out by the middle rib of fan shroud (picture Shroud Tab Outside) and the support rib of the upper radiator support tab (picture Upper Radiator Support Tab). Since there are no clipping mechanisms, I have come to the conclusion that the picture (Shroud Tab Outside) is the only way. The shop manual (page 6-368) says "Tuck the outboard corners of the lower cooling baffle under the support until it locks into place." There is no locking mechanism on either the fan shroud (picture Shroud Tab facing radiator) or the upper radiator support that neither I nor my neighbor can find. What am I missing? Or is the picture (Shroud Tab Outside) the correct way to install the upper radiator support?

jrprich

Is that a DeWitts radiator sticker? Perhaps the added thickness of the DeWitts is causing the top cover not to fit?

KGoodwin

Yes it is a DeWitts but the middle tab fits like a glove so I can't believe the thickness of the new radiator has an impact on the outer tabs. Looking at my pictures, I now see two reasons it can't work with the upper radiator support tabs on the outside. The plastic support structure on both the upper radiator and fan shroud tabs (curved backbone reinforcements) prevents them from fitting with the upper radiator tabs on the outside. I did follow DeWitts C5 recommendation to modify the fan shroud to provide a better fit on the outer edges (not necessary but recommended). I will have to say that the support I received from DeWitts was above and beyond normal customer service. I made a stupid mistake in ordering the radiator for the C5 and DeWitts had no problem undoing my mistake at no cost to me even though I felt I should reimburse them for the additional shipping costs.

jrprich

No negative intended about DeWitts. They make great rads!
But they are $$$$
Had a DeWitts in my 99 and tried to fit it into my 03 but GM changed the auto trans cooler ports in late 02 and was not able to build a solution

lionelhutz

I don't see how those 2 could fit together any other way.

vettenuts

Is this the first time, i.e., did you just install the radiator? I had instructions with my DeWitts on how to trim the pieces so they would go back together. I also had left side EOC so my trimming might be different than yours depending on what options you have in the radiator. Once I did the trimming, I had no issue with reassembly.

KGoodwin

My neighbor and I reached the same conclusion. Not only does the curved support rib on the backside of the radiator fan shroud prevent the upper radiator support from being installed on the outside but I noticed in my pictures that there is a curved support rib on the backside of the upper radiator support outer tabs that also interferes. I guess I got focused into thinking that if I wasn't having to beat it with a hammer, it wasn't being installed properly (lol). It was just too easy going together as shown in my picture. I will have to hijack another C5 to confirm.

KGoodwin

Yes I trimmed of the fan shroud recommended for the C5 by DeWitts. It keeps the fan shroud upper corners from digging into the radiator. I can still see some clearance between the radiator and fan shroud in these areas so they are not impacting the installation. I also followed a forum recommendation to use cardboard to protect the radiator coils during installation which was an excellent recommendation. I pulled the cardboard pieces out just before inserting the fan shroud in the 4 radiator tabs.