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Discussion Starter #1
Hello,

Researched about the issue and just wanted some input as well. When i bought the car, all four tires only had about 50% life left. I replaced the front two tires this afternoon, and every since then, the car has jerked at slow speeds on acceleration. If I am going 80mph on the highway everything is fine, but when I come from a red light and go, the car jerks in 1st gear; which might be the transfer case.


  • Should I go find two more tires to match the front two?


  • I don't believe the Trans Case Fluid was ever changed, so i might do that this weekend as well.

My thought is that since changing only the two tires in the front, it but more stress on the Transfer Case, which maybe the gear blew. Any thoughts?
 

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BM and V dub love!
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The difference in tire diameter is screwing with your transfer box. All 4 tires have to have even tread depth/diameters.

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Might jest have to wait till the tires settle in....harder compounds will seem like your driving on marbles till they get a good scuff as they say

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You need 4 tires of the exact same size AND brand/model. Even 4 new tires of the same size but different brands will have different sizes and cause the issues you describe. AWD is prone to issues if there is greater than 1% different in overall diameter. Welcome to AWD.
 

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Discussion Starter #5 (Edited)
You need 4 tires of the exact same size AND brand/model. Even 4 new tires of the same size but different brands will have different sizes and cause the issues you describe. AWD is prone to issues if there is greater than 1% different in overall diameter. Welcome to AWD.
Tuff. Ok, I will order another two tires that are exact size and make from the front two. In the mean time, is there a way to turn of the AWD till the new tires come in?

Edit: Do you think putting the car in SD in the mean time can help with the jerking?
 

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BM and V dub love!
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No way to deactivate the AWD temporarily. You could remove the front differential and axles... But I don't think that's what you're asking.

SD has no effect on the transfer case and will not reduce your symptoms.

Sent from my XT1650 using Tapatalk
 

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Discussion Starter #7 (Edited)
No way to deactivate the AWD temporarily. You could remove the front differential and axles... But I don't think that's what you're asking.

SD has no effect on the transfer case and will not reduce your symptoms.

Sent from my XT1650 using Tapatalk
Hey, thanks.

Looks like only solution at the moment is to get two tires that match the same from the front and go from there?

Edit: found 4 identical tires (235/55/17) for $140. Going to purchase them and mount them today and let you know of the outcome.
 

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Discussion Starter #9
Hey guys,

just wanted to say went to put on 4 matching tires yesterday night and now the jerking problem has significantly gone away, though there is some times when you can feel it; so it might be my transfer case is on the way out.


Will change the fluid when I do an oil change this weekend. Thanks everyone for the help.
 

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T-case fluid should be replaced every 30k, so you can estimate how many changes behind you are based on mileage.

Glad your driveability has improved. The gear can be replaced by itself, but usually throws lights or the tell tale clicking.
 

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It's not aggressive at all, it is standard replacement for driveline fluids, especially one for such a low amount of fluid getting quickly contaminated with clutch debris.
 

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I had a similar problem with my X5. Mechanic changed the transfer fluid and calibrated the transfer case and the ride is as smooth as a baby's ass.
 
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