View Single Post
  #142  
Old 01-30-2010, 01:24 PM
FunfDreisig FunfDreisig is offline
Member
 
Join Date: May 2009
Location: USA
Posts: 822
FunfDreisig is on a distinguished road
Quote:
Originally Posted by wch X5 View Post
My X5d also called for DEF at 900 miles. Dealer had me stop in and they found exactly what MINIz Guy's dealer found (100% in main tank, 66% in passive tank). The temperature was 35F outside....
I believe you. But this info simply does not make sense for a properly filled 35d DEF system....

We now have reports of two 35Ds to have their DEF warning trigger a 900 miles. In both cases the dealer reported the active tank @ 100% and the passive tank @ 66%.

AFAIK the DEF system holds a total of 6.5 gal: 2 gal in the main (active) tank and 4.5 gal in the passive tank.

So that would imply that these two 35Ds consumed 1/3 of the DEF in their passive tank in only 900 miles. 1/3 of 4.5gal = 1.5 gal IOW a DEF usage rate of 600 miles / gal of DEF => a full DEF system would only last 3,900 miles.

And yet we also have several reports of 35Ds that went 12,000ish miles without DEF issues.

Funf Dreisig
Reply With Quote

Sponsored Links