View Full Version : Automatic gearbox problem

Michael Dickson
05-09-2009, 04:51 AM
There is a fault in the gearbox of my 2005 Legacy automatic, causing a shuddering. The Subaru franchisees tell me it is partly or wholly caused by my having replaced one tyre with a sidewall bulge at a time when the rest of the tyres were, say, half way through their useful life, thereby creating a difference between the overall radius of that wheel/tyre compared with that of the other three.

Has anyone heard of this problem? Does it ring true? If so, then it will always be difficult to replace just one tyre!

05-29-2009, 07:17 PM
Is this AWD? I've heard similar issues from Suby dealers replacing one tire after 7,500 miles who made the client replace all 4 on AWD vehicles. Can you be more specific about the shuddering: only during shifts, while driving (always or sometimes), while idling?

If you wanna have some fun with the dealer, because I did this also, is ask for your money back. I asked him "If I can't wear one tire any more than any other, then why did you provide me a full-sized spare and instructions in the owners manual to do a 5-wheel periodic tire rotation?" I mean, if you put 7,500 miles on a set of four, and then rotate them using the full-sized spare in a 5-tire rotation pattern, then one tire will always be a slightly different diameter due to different mileage one each tire. So either the "different diameter due to replacing one and only one tire" is either a load of manure, or they lied in the owners manual and you can't do a full 5-tire rotation. Therefore you should get 100% refund plus penalties, right?

ps - I have 3 spares sitting alongside my house because a friend blew out one tire on a 09 Forester and the dealer refused to sell her one new tire, she needed all four replaced since one was bad. How many ways can you spell BS?

Michael Dickson
06-06-2009, 04:05 AM
Yes, my car is AWD. Interesting you say that Subaru dealer would not replace just one tyre. Here in Ireland, they do a 4-wheel rotation routinely on service, the spare tyre being the usual special little thin tyre that is often supplied with cars as a spare.

I have replaced all four tyres now, and the shuddering seems to have stopped as a result. It was happening at moderate and fast speeds, and the mechanic maintained he could feel it when idling, but I could not!

The only outstanding problem is that I still have the warning lights which, according to computer diagnosis, are showing problems in the automatic transmission. I have been in correspondence with the Technical Service Manager of Subaru Ireland (as opposed to the local dealer) about the whole problem, and I am now about to make an appointment for the car to be examined on his behalf, to see what should be done. He is saying that maybe it will be enough to adjust the settings relating to the warning lights i.e. ease the paramaters which trigger the illumination of those lights, to reflect slightly greater tolerance.

Meanwhile, it seems it is OK to fit just one tyre provided it matches the opposite wheel on the same axle with a diameter difference of no more than 2 mm, as measured not by a tread depth gauge (since different makes of tyre may vary although ostensibly the same size) but by a stagger gauge, a device which I think most garages and tyre centres do not have! Otherwise, both tyres on the same axle should be replaced, but I am not sure that they recommend replacing all four tyres!

Many thanks for your comments. I will advise you of the outcome.