Xi vs i

[nj325ci]

I'm looking at purchasing a CPO e90 sedan as a daily driver. A have another BMW for track and pleasure. For 25 years I've driven e30s and e46s and had snow tires on rims for winter. Trying to weigh doing the same with the e90 vs getting an X drive version. I typically keep my cars to around 180K miles. Does anyone have any input on the additional costs associated with the Xi vs RWD models over the long run?

Thanks, Bill

[afadeev]

I'm looking at purchasing a CPO e90 sedan as a daily driver. A have another BMW for track and pleasure. For 25 years I've driven e30s and e46s and had snow tires on rims for winter. Trying to weigh doing the same with the e90 vs getting an X drive version. I typically keep my cars to around 180K miles. Does anyone have any input on the additional costs associated with the Xi vs RWD models over the long run?

Thanks, Bill

Having just lease-returned E90 335iX (and previously owned E30s, E36s, and E46s with snow tires), I honestly can say that I regretted getting the iX.

I never had a problem with any of my Blizzak-shod RWD or FWD cars in snow and ice, and 335iX was no different. If I were to use it to drive up the mountain to go skying in Colorado, my answer may be different, but for driving around NJ, I saw no value from iX. Xdrive is a semi-AWD solution (open diffs with brakes used to minimize the wheel spin and keep the car pointed straight, but doing no torque transfer of any kind).

You pay the MPG and complexity penalties for AWD.
The former (1-2 MPG) may, or may not be, a big deal.
The latter would be a show stopper for me if I intended to own the car for 150+K miles.

alex

[RonG]

Xdrive is a semi-AWD solution (open diffs with brakes used to minimize the wheel spin and keep the car pointed straight, but doing no torque transfer of any kind).

This bit is incorrect--the xDrive transfer case is capable of directing 100% torque to the front or rear wheels, with a normal split of about 40%/60% F/R. You are correct that there is no lateral torque vectoring (except in a few higher-end models; the X6 is one I think).

Regarding maintenance costs, the differences do not amount to much: Transfer case, front differential, forward driveshaft and front half-shafts. The driveshaft is a non-issue. Changing the fluids is critical, especially for the transfer case which holds less than a liter of proprietary, expensive lubricant. Still, if done on the same interval as the rear diff (30K-75K depending on your driving profile and paranoia level), we're talking a few hundred dollars additional every other year or so, tops.

The front axles (specifically, the CV joints) appear to be have been significanty improved on the E90, in comparison to the E46's AWD system. On the E46 they were practically a wear item and could be expected to fail every 75-100K miles. The E90 does not seem to have that problem. However, it is still a component that takes a lot of abuse so, if keeping a car to nearly 200K miles, I would budget for a faiure or two. Replacement cost is around $800-$900 per side.

[BJerolimic]

Xdrive is a semi-AWD solution (open diffs with brakes used to minimize the wheel spin and keep the car pointed straight, but doing no torque transfer of any kind).

This bit is incorrect--the xDrive transfer case is capable of directing 100% torque to the front or rear wheels, with a normal split of about 40%/60% F/R. You are correct that there is no lateral torque vectoring (except in a few higher-end models; the X6 is one I think).

Regarding maintenance costs, the differences do not amount to much: Transfer case, front differential, forward driveshaft and front half-shafts. The driveshaft is a non-issue. Changing the fluids is critical, especially for the transfer case which holds less than a liter of proprietary, expensive lubricant. Still, if done on the same interval as the rear diff (30K-75K depending on your driving profile and paranoia level), we're talking a few hundred dollars additional every other year or so, tops.

The front axles (specifically, the CV joints) appear to be have been significanty improved on the E90, in comparison to the E46's AWD system. On the E46 they were practically a wear item and could be expected to fail every 75-100K miles. The E90 does not seem to have that problem. However, it is still a component that takes a lot of abuse so, if keeping a car to nearly 200K miles, I would budget for a faiure or two. Replacement cost is around $800-$900 per side.

don't forget there are other differences that lead to increased price on the parts, and additional labor to replace them... i.e. the control arms (both e30 and e46... I assume for e90 as well) and at least for the e46 there is an additional front ball joint that is separate from the arm. Additional labor is need to replace these more expensive parts as well, and they are not as friendly to DIY

I think possibly tie rod ends are also more for an Xi model... I wouldn't be surprised if shocks/struts were different/more, heck even the rotors on the e30 are more than a standard e30 if I recall correctly

[nj325ci]

Thanks everyone. All of this info has been very helpful.