auto trans. problrms

[78cummins-wagon]

lets see. i have a 1993 W250 with 3. 54 gears and an automatic 4spd. trans. i have already replaced the tps last year when it would randomly downshift on me and send me through the wind sheild. now the problm is towing. last week i had a 110TLB backhoe on our company trailer and had to use my truck (because our dura-trash was in the shop) to take it to the owners house. ever since then i have noticed that i have to have my foot in it a whole lot more to get it to move. to pull a normal hill its at 20+ pounds of boost. now i'm not sure if it was always that way or not but i'm not sure what to do. the truck has no tach so i'm not sure if the trans is just slipping a whole lot or what, but one things for sure with fuel prices as high as they are i dont want to be loosing any more than i need to. any help would be appriciated. o ya any one know of any trans upgrades? anyone know of a good lock up converter for it?

 

[tugboatphil]

78, That sounds like when my torque converter died. Have you dropped the pan to see if there's metal shavings? Whatever it is, it probably ain't going to get better.

 

[cerberusiam]

It definitely sounds like its working it pretty hard with 20+ lbs of boost on a "normal" hill. Now that definition of normal may take some clarification as "normal" is dependent on your locale.



TC, direct clutches, forward clutches, either or all can create what you describe. You have done well with 35" tires and 3. 54 gears on a stock (?) transmission. Those 2 are a killer without some mods.



As tugger says, drop the pan first and check things out.

 

[stoneagemaxx]

not to but in but cerberusiam what mods would you say need to be done to the auto to keep it alive w/35's and 3. 54's i'm going to be building a new trans here soon and will be installing a good TC hopefully converting to a 47rh for lockup and overall more strength, it will also have better clutches and hopefully some planetary upgrades, just gotta save up the $$

 

[cerberusiam]

not to but in but cerberusiam what mods would you say need to be done to the auto to keep it alive w/35's and 3. 54's i'm going to be building a new trans here soon and will be installing a good TC hopefully converting to a 47rh for lockup and overall more strength, it will also have better clutches and hopefully some planetary upgrades, just gotta save up the $$

Pressure, pressure, and more pressure, Line and clutch apply type. Doesn't have to be obnoxiously high but it needs to be considerably over the stock specs and not have leaks like a lot of the stock pieces do. Do the 5 or 6 clutch direct drum, shift kit, and band strut and it will be pretty good.

 

[78cummins-wagon]

last month i took the 35's off for gas milage reasons. there down to 285's now. but it had a good 3 to 4 thousand miles of toing with the 35's on it. could that have effected it?

 

[cerberusiam]

last month i took the 35's off for gas milage reasons. there down to 285's now. but it had a good 3 to 4 thousand miles of toing with the 35's on it. could that have effected it?

If you were towing some pretty good weight and the trans has some miles on it, yes that could have been the straw that broke it.



It only takes 15k or so on a commuter truck in traffic to start showing signs of damage on even a brand new truck. Stock pressures are for stock everything, including tires.

 

[carlwest]

I am on my second transmission, and this time with a Hughes converter. Also have a transmission temp gauge. The converter has made a world of difference. If you don't have a gauge, put one in. On a hot day and a hard pull it only takes a few minutes to cook the oil.

 

["Mad Max"]

My rig has 35's and 3. 54's, and I've dont the two big mods to the transmission - DTT converter and a deep pan. When I did the converter I noticed the transmission had non-factory tags on it - it had been rebuilt once before. The converter make such a big difference, and that goes a long way to keep the transmission cool and that'll add lots of miles to the transmission.

A good diesel rebuild/shift kit with an improved valve body will make an even bigger improvement to the performance.

I won't push the transmission too much more before having my transmission guy do the rebuild and valve body - I'm pushing pretty decent power through it and I don't want to kill it too soon.

- M2