Cadillac Owners Forum banner

1 - 18 of 18 Posts

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #1
Did anybody buy an XTS that has a spare. So long story short I didn't, they don't offer the kit, I had to piece it together, and am going to fabricate it myself. I have the rim, its an 18. But I don't know the tire size. If you have an XTS can you see what tire size you have? It should be on the driver side door jam a sticker that shows front back and spare, it should say the exact size tire that goes on your spare, if not it will say it on the tire itself. I found the GM part for the tire however i'd rather get it off tire rack its much cheaper. Thanks! Cheers!
 

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #3
Yes. The dealer ordered the spare as one of the options on my 2014 VSport Platinium.
Hey Xts Bill, I need the size of the tire. I have the rim, but I don't have the tire. The tire through GM is like $350 bucks so I was going to order it on tirerack.
 

·
Registered
2008 CTS4 DI Premium (SOLD) / 2013 XTS Luxury (TOTALLED) / 2015 BMW 328i XDrive Lux
Joined
·
1,970 Posts
I had my dealer swap out the inflation kit with the spare at no charge. (It is a donut spare wheel/tire)
 

·
Registered
2013 XTS-4 Premium
Joined
·
185 Posts
I could not resist having a look to see what I have on my '13 Premium! Guess what, I have a nice spare, "T135/70/R18 , 50psi" . There is a foam shape under the wheel with tools in it, and the depression in the floor looks big enough for a full size 'spare'. Maybe worth getting a 'real' full size spare (used)??
Hope this helps.
 

·
Registered
2008 CTS4 DI Premium (SOLD) / 2013 XTS Luxury (TOTALLED) / 2015 BMW 328i XDrive Lux
Joined
·
1,970 Posts
^^ I'll have to check mine again...does it look like a "medium" size donut? Either way, I may opt for a full size spare if it fits!! (I didn't think it would)
 

·
Registered
2020 XT6 Premium Luxury AWD - Horizon Red/Jet Black
Joined
·
268 Posts
Dealer ordered my car from factory to my specs, which included the spare. Just checked it. Size is: TPC Spec 620 T135/70R-18 104M
 

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #8
Thanks guys thats what I needed, that tire on tirerack is like 300 bucks :-( GM wants like 350 for the tire :-( after researching it. My example below is using my 20 inch rims. Check the specs. The T135/70R-18 is actually..

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
135/70-18 3.7in 12.7in 25.4in 79.9in 793 0.0%
245/40-20 3.9in 13.9in 27.7in 87.1in 728 8.9%

This temporary will throw your powertrain off significantly.

So you can use a

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
135/90-18 4.8in 13.8in 27.6in 86.6in 732 0.0%
245/40-20 3.9in 13.9in 27.7in 87.1in 728 0.5%

I cannot find that tire though....

So check this figure...

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
155/85-18 5.2in 14.2in 28.4in 89.1in 711 0.0%
245/40-20 3.9in 13.9in 27.7in 87.1in 728 -2.3%

So slightly off. Revs look good. The 155 tire will fit because it will fit a 4-4.5 inch rim and its 110 bucks on tire rack. Keep in mind my XTS did not come with that spare kit, so I am going to rip out all the foam and work at it like that I will keep you posted on if it fits good, if not I will get the 135/70/18 and return this tire. But lets compare both spares

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
135/70-18 3.7in 12.7in 25.4in 79.9in 793 0.0%
155/85-18 5.2in 14.2in 28.4in 89.1in 711 11.5%

11.5% size difference. another 10 inches in circumference. However that Diameter is the most important thing to see if it will fit in the trunk space. 3"... That is 1.5 Inches on each side.... I actually think its going to fit. Anybody who has a spare, can you measure 1.5 inches extra from the end of your tire?
 

·
Registered
2020 XT6 Premium Luxury AWD - Horizon Red/Jet Black
Joined
·
268 Posts
Just checked mine for that 1.5" of space. Sorry to disappoint you, but there is slightly less than that amount of space surrounding the tire. On top of that, the cavity curves in as it goes to the bottom, leaving even less space.
 

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #11
Just checked mine for that 1.5" of space. Sorry to disappoint you, but there is slightly less than that amount of space surrounding the tire. On top of that, the cavity curves in as it goes to the bottom, leaving even less space.
Ugh I already ordered that tire... I think I can get it to fit. I do have take out the foam stuff. I'll let you know what happens!
 

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #13
As Lencarguy stated, it did not fit. It was by 1/2-3/4 of an inch. So the tire wouldn't go down all the way. I just said screw it, ordered the Maxxis tire directly from their site, which is cheaper than the tire rack tire which is a bridgestone. I am returning the Continental to tire rack
 

·
Registered
2013 XTS-4 Premium
Joined
·
185 Posts
As Lencarguy stated, it did not fit. It was by 1/2-3/4 of an inch. So the tire wouldn't go down all the way. I just said screw it, ordered the Maxxis tire directly from their site, which is cheaper than the tire rack tire which is a bridgestone. I am returning the Continental to tire rack
Does this mean that if I get a nail in my (19") tire, and put the compact spare on, then I won't be able to put the dead one back in the hole? I'll have to find room for it among the luggage until I get it fixed? Gee, it would not have hurt Caddy too much to give us the extra 3/4! I'm assuming we are referring to 19", not 20" wheels not fitting? I wonder if the hole is same as on Impala, and is sized for it's 18" wheels??
 

·
Registered
14 ats
Joined
·
94 Posts
Discussion Starter #15
As Lencarguy stated, it did not fit. It was by 1/2-3/4 of an inch. So the tire wouldn't go down all the way. I just said screw it, ordered the Maxxis tire directly from their site, which is cheaper than the tire rack tire which is a bridgestone. I am returning the Continental to tire rack
Allow me to retort, the tire does fit. The 155/85-18. However flat. I emptied, it still is slightly too big by like 1/4" if that. This shouldn't be a problem to be honest. I am gonna roll with it. I am going to return the Maxxis tire. The air compressor that comes with the car will go up to 80PSI. I am sure you do have to let it cool but I think its worth a shot. I also have a battery jump starter by Stanley that I bought on Amazon that has a built in compressor and it goes up to 120 PSI. I keep this in my car at all times as well.

----------

Does this mean that if I get a nail in my (19") tire, and put the compact spare on, then I won't be able to put the dead one back in the hole? I'll have to find room for it among the luggage until I get it fixed? Gee, it would not have hurt Caddy too much to give us the extra 3/4! I'm assuming we are referring to 19", not 20" wheels not fitting? I wonder if the hole is same as on Impala, and is sized for it's 18" wheels??
Well if the tire is flat you should be able to. Just its going to bulge up like 2/3 inches, read my last post. It shouldn't matter if you have 20s or 19s. I have 20s, but the tire size on yours would have a bigger sidewall. Mine are 245/40-20, yours are probably 245/45-19. So that will probably run slightly smaller than the 20s. The tire I put on the 155/85/18 is slightly bigger than 245/40/20. By 2%. So I would think you should be able to get it to fit. I would be concerned about scratching the rim when placing it in there. Either way I wouldnt.
 

·
Registered
2014 XTS P4
Joined
·
2 Posts
Our 2014 XTS P4 has one of those crappy little donut spares. We didn't order it and as I understand
it, it normally does not come with a spare [ a weight savings ya ] know but ours has one.
 

·
Registered
2008 STS V6 DI, 2014 XTS Premium AWD V-Sport
Joined
·
120 Posts
2014 XTS Premium V-Sport with inflation kit, no spare.

That would be a pain to use. I bought a can of pressurized Green Slime from Amazon that will do the same job as the inflation kit without the hassle. Just have to make sure the tire is fixed with a patch (not a plug) and all the water soluble Green Slime is washed out of the tire. Remarks on can state that the Green Slime does not effect the Tire Pressure Sensors.

Just hope if I need it, it's for a flat not a sidewall issue, then again the same would hold true for the inflation kit.

I wonder what roadside service does in a case like that?
 
1 - 18 of 18 Posts
Top