I believe the engines are mounted longitudinally to accomodate the passats with 4motion. As far as the problems are concerned, I've only read a comparison on the sludge issue. Apparently sludge is less common in the golf/jetta, but I'm not sure of the reason.

 

One reason is that the Golf/Jetta have higher oil capacities. Our Passats even have a smaller oil capacity than the smaller Audi A4, which was mounted logitudinally too.

 

IIRC the trans configuration allows one to get greater HP vs the long congfiguration.

 

equal length axles are awesome too

 

Our Passats even have a smaller oil capacity than the smaller Audi A4, which was mounted logitudinally too.

really? ive never heard this...surprising because the engine codes used on the A4 and Passat are exactly the same:crazy:

 

I thought they were the same engine too.....just that the b5.5 had a longer frame.

 

i figured it was to make the cars smaller,if the jetta,golf was longitudinal then the car would be bigger from the windshield to the front.whereas the jetta golf is smaller so the engine is tranverse

 

really? ive never heard this...surprising because the engine codes used on the A4 and Passat are exactly the same:crazy:

I might be wrong (and it is certainly possible), but I thought our cars actually had an oil capacity (originally as in the manual) of like 3.7-3.8 quarts. The manual of the 2001 A4 my sister has lists 4.2 quarts. The newer big filters has raised our capacity to something like 4.2 or 4.4 quarts, and the A4 uses around 4.4-4.5 quarts.

Of course, I'm basing this off of what I remember and what I just searched quickly. Once again I might be wrong and they might be wrong. Hope that helps =).

http://www.passatworld.com/forums/showthread.php?t=167732

 

the original oil capacity of the B5 A4 was 3.7quarts, which was changed to 4.2 with the larger filter. same engine

 

My sister's 2001 owners manual called for 4.2 quarts (I looked it up on Friday) when I took it into the shop. This is the weird A4 (B5 body style), but updated with the 170 hp engine (maybe they went to the bigger filter sooner?). My 2003 Passat GLS called for 3.7 or 3.8 in the manual. The bigger filter brought the 2 to very similiar capacities.

I am not trying to argue (just in case it might seem like it), I was just giving you the information that I have (not that it's important), considering that both the A4 and Passat both have about the same oil capacities with the bigger oil filter.

I just realized that I might have been reading the liters value for my passat. From my own link it said 3.7L, which is like 3.9 quarts. I am still sure that the A4 said 4.2 quarts though.

 

If one adjusts for small model year variations, A4 and Passat 1.8Ts should have roughly equal oil capacities. The transverse 1.8Ts (Jetta et al.) do have a full 5-quart sump, and "sludging" / coking IS less common in these, because the larger sump keeps the oil marginally cooler and because each oil molecule makes fewer trips through the engine with a larger sump. If a 5k mi / 8k km OCI is appropriate with a 5 qt. sump, something like 3.5k mi / 6k km would make sense with a 4 qt. sump.

 

Are the Audi A4 as prone as the Passat for oil sludging? Maybe ModifiedA4 might know? =)

 

Are the Audi A4 as prone as the Passat for oil sludging? Maybe ModifiedA4 might know? =)

yes.

 

Transverse (Jetta) is arguably better for front wheel drive; you are already spinning the shaft in the same direction as the wheels... easier to transfer power.

The only reason I can think of to go longitudinal (Passat) is to accomodate transfer of power to the rear of the car. Our car is an A4 with the rear drive line removed (unless you happen to have 4Mo). It is not the most ideal design IMO.

 

Are the Audi A4 as prone as the Passat for oil sludging? Maybe ModifiedA4 might know? =)

Yes, when I went to a local VW Indy, I asked him several questions (sounding very paranoid) about the slidge issue and he showed me a 1.8T Audi A4 that was awaiting a new engine (or at least significant amounts of parts for the old one).

 

The reason the engines are mounted longitudinally in the Passat is because it is Audi based. Audi has mounted their mounted their engines longitudinally since the 1960's except for the A3, TT and some small cars not sold in the U.S. which are actually based on VW platforms.

 

Are the Audi A4 as prone as the Passat for oil sludging? Maybe ModifiedA4 might know? =)

yes, since the engines are exactly the same...same problems.

what is interesting is that you rarely see a sludging post on audiworld, most A4 owners switch to "synthetic and forget it".

Long before sludging was an issue, coking of the oil in the turbo feed line was the issue, so most A4 owners switched to synth for that reason and basically sidestepped the sludge issue.

also, sludging is much less likely on a well maintained engine, and all B5 A4s had free dealer service for the life of the warranty...this also probably prevented alot of sludge cases.

 

That's cool, thank you all for the information.