Towing capabilities of automatic gearbox

Rex Surewood · Post by **Rex Surewood** » Sun Aug 31, 2008 2:18 am

I'm looking for peoples opinions on towing trailers with the 412 Auto. I know what the books say, but in real life - what's considered the maximum towing weight when it still has to be pretty undramatic and safe to drive?
And how does the gearbox take it after 35 years of use?

The thing is, that I would like to tow about 2700 lbs around longer distances a couple times a year, but I want it to be a fairly smooth ride.

In your opinion - Is the 412 up for it?

Thanks.

raygreenwood · Post by **raygreenwood** » Sun Aug 31, 2008 10:54 am

I would not tow anything over about 500 lbs with a 411/412. There is just not enough power, torque or cooling for that. 2700 lbs is more than the car weighs.
The automatic transmission should be fine for towing that much....but if it has not had in service in its 35 years...I would for sure replace the seals between teh final drive section and the transfer case. Those should be replaced every 7 years or 70k miles. I would also put the gauges on the hydraulic ports and give it adriving/pressure test. Its probably time to readjust the main pressure. Ray

Rex Surewood · Post by **Rex Surewood** » Tue Sep 02, 2008 2:44 pm

There's lots of power and cooling, so the only thing i'm concerned about, is the gearbox. But properly tuned and serviced it shouldn't be a problem?

Thanks

raygreenwood · Post by **raygreenwood** » Wed Sep 03, 2008 4:43 am

Is this the stock engine and cooling system? If so...sorry to be argumentative but there is not enough power and cooling. Most especially with the high standard final drive gearing that these cars had.

If you changed to a bus or vanagon converter....you would have better mechanical advantage and it would not be so hard on the engine.

The other main cooling issue is that there is no transmission cooler on this unit. The factory cars already ran fairly hot in the gearbox.
You may a particular advantage being in Denmark....but in the warm areas of my country, towing with a 411/412....or even carry a maximum load (trunk full and four people) in warm climate could be a recipe for disaster.

The main factor in this...is the factory state of tune. If its a rebuilt and heavily improved engine (even in overall stock displacment and compression)....this is much less of an issue. Since you have not told us anything of your engine...I can only assume its stock.
The stock state of tune with either D-jet or twin carbs will NOT safely tow 2700 pounds. This brings it more into the weight realm of driving a type II van with a type 4 engine. We all know the overheating and overloading issues those suffered....even with afour speed.
Just some things to think about. Ray

Rex Surewood · Post by **Rex Surewood** » Wed Sep 03, 2008 12:02 pm

Thanks for the info Ray. The car has no engine in it now, so I'm going to build one for it - with the power needed.

But I'm gonna concider pro's and con's with the whole thing.. Thanks.

raygreenwood · Post by **raygreenwood** » Wed Sep 03, 2008 1:53 pm

Oh!...different story then!..Yes, the gearbox will hold up well...with a bit of a tune up 9some new seas and a slightly higher stall rpm converter and an adjustment to the main pressure to match the vacuum signature of your new engine.. Even a 1.7L with improvemnets (better cam, bigger valves, external oil cooler, better exhaust and tweeks to the injection) ...should do fine to tow a decent load. Ray

Rex Surewood · Post by **Rex Surewood** » Thu Sep 04, 2008 9:31 am

That's better to hear!

A Vanagon converter that is?

Thanks

raygreenwood · Post by **raygreenwood** » Thu Sep 04, 2008 10:14 am

Do a quick search in teh 411/412...or maybe type 4rum. I think piledriver and a few others have noted which converter to use in several posts. Its either from a late bus or vanagon. But....basiclaly it shifts the lock-up/stall point up teh rpm range by about 1000 rpm...so you are in a better torque band when taking off from a light or shifting gears.

On highway cruising...the type 4 can indeed tow. its the starting out and in traffic gear to gear shifting where load becomes and issue. Keeping the rpm's up will be key. Accomplish that while keepingt it cool and you should have few problems. Ray

vwfye · Post by **vwfye** » Thu Sep 04, 2008 3:06 pm

who was it that has the picture of the 412 towing on a trailer another 412? did they have issues with heat?

raygreenwood · Post by **raygreenwood** » Fri Sep 05, 2008 4:50 am

The 411 and 412's all had issues with heat even when not towing anything. Of course 90% of that was because of the huge variances the cars had in factory tuning specs....and from the really poor cam and exhaust muffler design which traps a lot of heat in the heads.
The real question with towing...is whether anyone who has towed with a 411/412 had the proper instruments onboard to prove that the did NOT have heat problems.
You need at least a CHT for each cylinder head and an oil temp sensor. Ray

Rex Surewood · Post by **Rex Surewood** » Sat Sep 06, 2008 2:14 pm

Thanks very much for the info.

ubercrap · Post by **ubercrap** » Thu Sep 11, 2008 10:18 am

vwfye wrote:who was it that has the picture of the 412 towing on a trailer another 412? did they have issues with heat?

I believe that was Wally. Adrian Pienaar had some images of towing a bay window bus on a dolly with a Type 4. These were manual trans. of course. I think the difference in towing attitudes is due to the nature of the size of the countries. The United States is gigantic compared the Netherlands, South Africa, Denmark etc... If one needs to tow something across the country here, the speeds and distances here are brutal on tow vehicles. Or am I crazy?

raygreenwood · Post by **raygreenwood** » Thu Sep 11, 2008 10:37 am

Uber....I think you are hitting on some of the same issues I have.
For isntance in Texas, Oklahoma, New Mexico...and perhaps most of the central part of this country....in wram weather and at the highway speeds you must observe to keep from "dying from behind".......towing significant weights with ANY 4 cylinder vehicle is a no-no. In fact a great many auto maufacturers do not ecocomend towing much if anything with any engine under 6 cylinders.
Though most owners manuals...even my rabbit convertible....listed towing capacity at only a few hudred pounds . Ray