Help with my transmission

[bkahler]

Originally Posted by Keyair

Agreed!
Putting a OD transmission in is not cost effective even doing it yourself...
Nor is putting a diesel in...

But we are not logical about what we love!
Which is why I have a 4L80E under my bench...
It looks good, but I am planning to rebuild it... at $175 it was a steal!

Steve, I've got a 4L80E out of a Chevy box truck sitting on my shop floor as well! Once the Argosy is up and running with the original transmission I'll then take the time to swap in the 4L80E. Shouldn't be as difficult for my Argosy as the parking brake(s) are located at the rear axle so I don't have to mess with the transmission mounted brake.

Brad

[PeterH-350LE]

Originally Posted by Keyair

...

The next step would be to replace it with the next generation transmission... The 4L80E, or its HD counterpart, the 4L85E.
....!

Question for Keyair and Brad:
If the TH400 in our Motorhomes is really a TH475 (heavy duty version of the TH 400), why would you want to put the 4L80E in as a replacement instead of the 4L85E?

[bkahler]

Originally Posted by PeterH-Airstreamer

Question for Keyair and Brad:
If the TH400 in our Motorhomes is really a TH475 (heavy duty version of the TH 400), why would you want to put the 4L80E in as a replacement instead of the 4L85E?

Peter, my Argosy only weighs around 8500 lbs so a 4L80E is well within it's capabilities. Personally I think even with a 310 a 4L80E would be probably sufficient.

Per the Wiki site: "The 4L80E was rated to max GVWR of 18,000 (Axle and vehicle dependent)[2] Applications"

I'm thinking the 310 is definitely less than 18,000 lbs. and even towing a car on a trailer with my Argosy I should be well within it's weight rating.

Brad

[Keyair]

Beat me to it Brad!

Lucky you, that you don't have to deal with the parking brake issue!

Peter, you are correct, and everything I have read about the 4L80E and 4L85E points to them being brothers like the TH400 and 475. I gather that the 85 has straight cut planetaries too.

[german6563]

Hello everyone
thank you very much for all the information I received.
My transmission is 31 spline and the other I got is 27.
here in Germany is quite complicated to get a house of HD, so ask if the housing of the TH 400 with 27 spline is equal,
Only I have to take him to a professional to change places with all new elements and ready
of all professionals here wondering, none could tell me if the houses are the same, and do not want that start to experiment with my transmission
Herman

[J. Morgan]

The 31 spline shaft is maybe a little stronger, the case and internals are the same except for maybe the removable tail shaft housing.

The difference in strength between the 27 spline and the 31 spline shaft is not enough to worry about in my opinion.

If I were in your situation, I would carefully select a yoke to fit your transmission and driveline and put it in the RV.

If your truck uses 1350 series universal joints this will be easy, if it uses 1410 series universal joints this will be difficult or impossible unless you are willing to modify the driveline, and at this point things start becoming more trouble than swapping for a 31 spline transmission.

[german6563]

thanks for that information, I'll see if I really get an HD so I have no more problems
Herman

[german6563]

Hello everyone
I found a digital transmission with 32 spline (my transmission is 32, it was my mistake to see only 31)
The transmission is a 1988 Suburban.
you there is a difference between the transmission of suburban and believe my transmission?
Herman

[J. Morgan]

If you bought a computer controlled transmission, you will need a wiring harness and processor to make it work, a lot of expense and trouble.

88 was around the transition time to electronic controls. If the transmission is a THM 400 it is NOT computer controlled, if it is a four speed OD, I don't know if it needs a computer or not.

[J. Morgan]

If the 88 transmission is from a 3/4 tom Suburban you SHOULD be good.

It should be a THM 400, and therefore not electronically shifted.

[Keyair]

I had an '87 and a '90 3/4t Suburbans.... Both had TH400.

[german6563]

Hello everyone
I want to thank all the support I have been given here.
It was difficult but not impossible to buy the correct transmission yesterday for my RV, so now get to work to place and to make the first ride
Herman

[Grosspoluter]

I to would like to thank everyone here for the advice and insights
I have since had the uncracked trans rebuilt by Aamco
This picticular shop had a lot of good reviews, I know everything YA here on the Internet isn't nessarly true, but also at some point you have to trust someone.
After the rebuild I took the rebuild and the 345 to a truck and RV shop in rockford illinois (where the 345 is stored) it is now in the shop having the transmission switched out, if the repair is good I'll feel a LOT better about taking trips in the 345.... Of course I'm now reading the thread about tag axles and have new things to worry about

[german6563]

Hello people
the transmission is placed, and now want to put an extra cooler,
Now I need your help once again
My idea is to put the cooler after the original cooler means, transmission, original cooler and after the extra cooler.
transmission now come two pipes one up and one down, which is the output of which is the oil that returns from the cooler to the transmission?
Thank you
Herman

[Keyair]

Originally Posted by german6563

Hello people
the transmission is placed, and now want to put an extra cooler,
Now I need your help once again
My idea is to put the cooler after the original cooler means, transmission, original cooler and after the extra cooler.
transmission now come two pipes one up and one down, which is the output of which is the oil that returns from the cooler to the transmission?
Thank you
Herman

Herman, that is a wise choice.

The UPPER cooler line is the return, and the LOWER is the feed.

TH400
Fitting Location..... Thread Size..... Flow Direction
Upper .................... ¼" Pipe............. Return/in
Lower..................... ¼" Pipe............. Cooler feed/out

[german6563]

Hello
Keyair thanks for your help, it helped me a lot.
Now I need help I think the last, someone has a diagram from the shifter to the transmission, is that when disarmament I now can not remember how it goes connected to the transmission,
I try to connect but I saw that there are two positions and which is not the correct .I look on google, but unfortunately nothing
Thank you
Herman
PS I just need to make that connection and can give the first lap with my RV

[Keyair]

This might help...

[german6563]

hello Keyair
Thanks for the picture, helped me a lot, of course already placed
again thank you very much
Herman