1987 R10 Radiator Leak

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

rcotner

Junior Member
Joined
Oct 6, 2023
Posts
13
Reaction score
6
Location
Pennsylvania
First Name
Ronald
Truck Year
1987
Truck Model
Chevrolet Silverado R10
Engine Size
305 ci
I have a few pin holes just below the fill cap on my radiator and they appear to be on the corner closest to the grill. I attempted a fix with JB weld for radiators and apparently missed a couple spots or didn’t apply it heavy enough as it is still leaking slightly from same area. Trying to seal it again for the second time. If this doesn’t work does anyone have any thoughts on where I could purchase a new radiator (copper style) or would it be best to do aluminum and where to purchase exact replacement to drop in with no issues?
 

CountKrunk

Full Access Member
Joined
Aug 3, 2023
Posts
439
Reaction score
1,020
Location
SW VA
First Name
Count
Truck Year
1984
Truck Model
C20 Custom Deluxe 3+3
Engine Size
v8 350
A quick google showed a lot of options. Have you looked into any of those yet?
 

rcotner

Junior Member
Joined
Oct 6, 2023
Posts
13
Reaction score
6
Location
Pennsylvania
First Name
Ronald
Truck Year
1987
Truck Model
Chevrolet Silverado R10
Engine Size
305 ci
I have looked at Auto Zone, Advance Auto Parts, Napa, lmc truck. All seem to have their own varied models. Just trying to stay away from plastic. Not all give a very good description of type of material.
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,456
Reaction score
8,715
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
Learn to solder. Acid core solder and a propane torch will fix it.
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
2,029
Reaction score
2,938
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
If a radiator shop is close may be a re-core? That used to be the way it was done before disposable radiators came on the scene.

Last one I needed got a plastic/aluminum rad. Even though they aren't original, heat transfer is better.
 

T-roy K10

Member
Joined
May 9, 2023
Posts
48
Reaction score
76
Location
mississippi
First Name
Troy
Truck Year
1985
Truck Model
K10
Engine Size
350
I replaced mine with the largest radiator they offered at LMC truck. Didn’t know I was getting an aluminum/plastic one, but it does cool better than the original. I also had to order the larger rubber bushings and top bracket (only about 20 bucks) because the radiator is thicker than my original.
Some minor mods to the shroud and done, a cooler motor. Just hope it lasts.
 

chevytech87

Full Access Member
Joined
Dec 6, 2022
Posts
99
Reaction score
230
Location
Tomball, TX
First Name
Brandon
Truck Year
1987
Truck Model
GMC R1500
Engine Size
305
I replaced mine with the largest radiator they offered at LMC truck. Didn’t know I was getting an aluminum/plastic one, but it does cool better than the original. I also had to order the larger rubber bushings and top bracket (only about 20 bucks) because the radiator is thicker than my original.
Some minor mods to the shroud and done, a cooler motor. Just hope it lasts.
Got a part number for that bracket by chance?
 

Redfish

Full Access Member
Joined
Nov 6, 2021
Posts
2,658
Reaction score
14,316
Location
Prairieville, LA
First Name
Andrew
Truck Year
1987
Truck Model
V1500
Engine Size
350/5.7
I just replaced mine and I was In A Hurry with no time to explore options. I went with a direct replacement from O'Reilly's because I Needed It Right Now! and couldn't be picky.

I know we all hate the idea of plastic...but my 2500HD Duramax came with a plastic and aluminum radiator and it works just fine. The 2500HD Duramax before this one had a plastic and aluminum radiator. All of the new GM trucks come from the factory with plastic and aluminum radiators.

For me there were 3 major criteria.
1. Liquid had to remain INSIDE the radiator.
2. The engine could not overheat.
3. It wasn't a shiny, obvious aftermarket replacement.

While I would have liked a radiator that was all metal and looked exactly like the one I removed (minus the leaks and corrosion), I am not unhappy with what I got. And it was not expensive.
 

T-roy K10

Member
Joined
May 9, 2023
Posts
48
Reaction score
76
Location
mississippi
First Name
Troy
Truck Year
1985
Truck Model
K10
Engine Size
350
Got a part number for that bracket by chance?
Sure do.

32-0988 upper panel radiator mount. $22.95

32-0972 radiator mounting pad $4.95 (need 4)

32-2947 radiator $299.00

Oreilys has a radiator for less that looks to be the same as the one from LMC, but I’m not positive. I would look up the measurements to make sure.
 
Last edited:

T-roy K10

Member
Joined
May 9, 2023
Posts
48
Reaction score
76
Location
mississippi
First Name
Troy
Truck Year
1985
Truck Model
K10
Engine Size
350
I just replaced mine and I was In A Hurry with no time to explore options. I went with a direct replacement from O'Reilly's because I Needed It Right Now! and couldn't be picky.

I know we all hate the idea of plastic...but my 2500HD Duramax came with a plastic and aluminum radiator and it works just fine. The 2500HD Duramax before this one had a plastic and aluminum radiator. All of the new GM trucks come from the factory with plastic and aluminum radiators.

For me there were 3 major criteria.
1. Liquid had to remain INSIDE the radiator.
2. The engine could not overheat.
3. It wasn't a shiny, obvious aftermarket replacement.

While I would have liked a radiator that was all metal and looked exactly like the one I removed (minus the leaks and corrosion), I am not unhappy with what I got. And it was not expensive.

and probably the same one I got from LMC truck for less money.
I also ordered one from O’reillys ($200. I think) but when it came in I measured it and knew it wouldn’t fit in my brackets, so I ordered the one from LMC thinking it would be all metal like the original. Well they looked like the same Part. That’s when I researched it and found I could make it fit with the correct brackets and bushings From LMC.
 

Finkaire

Finkaire
Joined
Dec 28, 2021
Posts
454
Reaction score
746
Location
California
First Name
Loren
Truck Year
1984
Truck Model
Silverado c10
Engine Size
305
i bought a cold-case and it didn’t fit, bought a NOS Modine radiator on EBay and it didn’t fit. Tired of messing around I took it to a radiator shop and had it re-cored. Are you sitting down……. $850. No regrets
 

Goldie Driver

Full Access Member
Joined
Mar 19, 2018
Posts
4,042
Reaction score
6,634
Location
Houston, Texas
First Name
Britt
Truck Year
1980
Truck Model
GMC K1500 Suburban
Engine Size
350
i bought a cold-case and it didn’t fit, bought a NOS Modine radiator on EBay and it didn’t fit. Tired of messing around I took it to a radiator shop and had it re-cored. Are you sitting down……. $850. No regrets

Price seems steep, but hopefully they built you a 4 core. I had my metal one re-done as well- OE end tanks on a 4 core as the original 3 row was too far gone. Plastic tanks and aluminum cores work great and are lighter but just not the same in my book.

YMMV
 

T-roy K10

Member
Joined
May 9, 2023
Posts
48
Reaction score
76
Location
mississippi
First Name
Troy
Truck Year
1985
Truck Model
K10
Engine Size
350
I think guys are way too hung-up on how many cores a radiator has. I was too until i compared the original 3 core to the new 2 core. By ”core”, apparently they’re referring to the horizontal rows of tubing. My original had 3 rows of tubing that are only about 1/2“ max each. the 2 rows in the new radiator are probably over 1”. that means the old 3 core is 1.5” thick and the new 2 core is 2 1/4”. That means more surface area (cooler water temp) with 2 than there was with 3. This is obviously the case because the truck runs cooler with the 2 core than it did with the 3 Core.
 

Forum statistics

Threads
44,175
Posts
950,925
Members
36,297
Latest member
DrewS4
Top