Suncoast transmission installed into my 1st gen

[CHanstedt]

I know transmission’s are a touchy subject with this group, so I’m just going to post my experience, and just the facts. (Photos attached)



My 92 truck has 192,000 miles (who knows if the 518 in it is the original?) and the torque converter stalls way too high to take any advantage of the power curve and the other big concern is that it bleeds all over the driveway when I park it. My motor is totally stock.



I shopped a few companies:



1. Phoenix Transmission (local shop):

$1500 with a new torque converter

90 day warranty



2. Suncoast

$3113 – trans, converter and DD pan

$800 core

$500 shipping to Phoenix

3 year warranty



3. ATS

$2770 – trans, converter and DD pan

$1200 core

$460 shipping



4. DTT

No cores in stock, I would have to ship them mine and wait for a few weeks. I didn’t pursue this any further.



My choice:

I ended up buying the Suncoast transmission. A local diesel shop (A to Z Diesel in Mesa, AZ) wanted $650 to install. I decided to do it myself, I do have the tools and equipment…. and a few hours to do it.



The Suncoast unit arrived in 7 days in a big plastic tote. I used my engine hoist and an old 5 point harness belt from my race car to get the unit out of the tote. This transmission is HEAVY!



I used (4) 12 ton jack stands to secure my 2 wd - D350 dually about 40 inches off the ground. The stock height of my truck is really low.



R&R transmission:

This is my first transmission experience with a diesel, I’ve done lots of muscle cars and race cars. Nothing stands out as being truly unique other than you need both a metric and standard set of wrenches. I was amazed at how close the body of the truck sits real close to the frame, making it very difficult to get at the mounting bolts. I bought an extra 14mm closed end wrench and bent it on my press into a 45 degree angle so I could get these bolts without tearing up my knuckles. There is no room to use any kind of flexible socket.



transmission fluid:

After installing the unit I called Suncoast to see what fluid they recommend and how much to use. They said break it in with Dexron and then use what ever you want. Apparently their units are insensitive to the type of fluid you use. I ended up using 19 quarts to get the proper level on the dip stick with the truck in neutral.



How does it run?

Suncoast unit runs very different from the “stock” unit. Stall speed is very low and the truck gets to utilize it’s power band and the motor actually runs through the RPM as opposed to before the motor went right the governor and then the truck started to move. I have not had the opportunity to tow with it yet, but there is a race coming up so I’ll hook up the race car trailer and hope to feel an improvement.

I did notice a big improvement in fuel mileage. On the freeway in 110 degree heat from Phoenix to Tucson I got an honest 21 mpg, repeated a few times. In the past 16 mpg was the best I ever got. So maybe the old transmission and converter truly was junk.



The final actual cost:

As read from my invoice

transmission $2195

T. Converter $683

DD pan $235

Core $800

Freight $307



Subtotal $4220

Core -$800

Return Freight $281



Total $3701



I’ll assume the return freight was cheaper because the original transmission is much lighter, or the Suncoast is that much HEAVIER!



So far so good and I am happy with the Suncoast unit. They are expensive for a guy like me. I am an aerospace engineer and we make peanuts…. and our jobs are being sent to India and Singapore at that. So a purchase like this is very significant to me, who knows if I have a job come Monday.



I’ll be the first to report any problems, if any.



Over and out!

 

[jimnance]

Thanks for the post. It makes me wonder if my 518 is stock. With 130,000 miles on the truck (no idea about the transmission) the shifts are firm but not abrupt. Kind of reminds me of the shifts in my '99 after the valve body was reworked. Shifts always come by 2100 RPM even under hard acceleration. The engine is stock.



One slight concern is that the engine seems to like 2,000 RPM. When everything is in cruise at say 60 MPH I'll be showing about 1700 RPM. When I step on the accelerator the RPM's go to 2,000 and stay there until the truck reaches about 70 MPH at which point the RPM's again rise with speed. Could this be a clutch issue with the torque converter?

 

[832]

Is that TC a lock up or non-lock up version? I am planning to do mine in my '93 and have never been a big fan of the stock transmission.

 

[jimnance]

Honestly, I'm not certain. I know the transmission has overdrive, and I was assuming that the transmission had a lock up on the torque converter. In the '93 model does anyone know if T/C lock up was an option or standard?

 

[Forrest Nearing]

non lockup...



that's a sweet lookin' rig you got there! I know those trannies are expensive, but it's a lot cheaper than a new truck, and it oughta last forever

 

[CHanstedt]

The Suncoast Torque converter is a non-lockup unit. You can tell by the price... $600-something. 2nd Gens have a lockup converter and the price doubles for those units.

 

[dpuckett]

Mom had her transmission rebuilt locally (cheaper is better), and he put in a stock reman T/C . Still getting 18mpg hwy; I got 21-23 6yrs and 130K ago. Glad you like it. Nice looking truck you got there. 21mpg out of yours with a new auto; I ought to be able to see 23 with mine (manual, not quite as big) with a pump redo.



Daniel

 

[832]

Can you put a lock up TC in a 518 transmission? Curious?

 

[BushWakr - RIP]

CHanstedt makes a couple good points... .....



The aftermarket trannies/TC/VB's make a nice difference in mileage (assuming a reasonably tuned pump and driver... . ya. . right... .

Second, they give the engine a proper operating range for it shine... . the torque band in these trucks is lower than any of the OEM transmission units could ever hope to utilize period. .

Third, throttle response is a bit of an eye opener..... the truck actually responds to throttle changes very quickly... . it's the best of both the manual and auto world... you get solid response, good power transfer, and no levers and peddles to mess with. .



You do need to tweak and tune a bit though... the TC's are usually tight enough that you need to improve your low end fueling a bit to get it outta the hole so to speak. .



... this was a "driveby" post by me..... you guys behave yer'selves .....





pb...

 

[dpuckett]

If you come up with the computer to control it, you can install a lock up.



-DP

 

[Got Smoke?]

Am I the only one thinking... ... "man I hope he doesn't hit that DD pan on anything"



Good write up!

 

[Moab4x4]

Thanks for the writeup!!

Am I the only one thinking... ... "man I hope he doesn't hit that DD pan on anything"



Good write up!

Me too!, But I 'wheel in my 4x4 and this one tows a race car. I think the only worry might be to the the jackrabbits crossing the road. :-laf

I am curious where the front suspension falls in there though height wise off the pavement. Especially with the comment about the low riding truck.



BTW, I really appreciated the write-up. Makes me wonder what I would see jsut replacing the TC as my transmission seems to be fine and it is hard to pay $$ to replace what aint too broke.

 

[CHanstedt]

My original idea was to only replace the TC but I thought, if I am going to pull the transmission, I only want to do it once. It took me a few days to stomach the finances, but now I have piece of mind with this transmission. My driveway looks better too. No more blood... .



The DD pan on the other hand, has low ground clearance. I haven't hit it on any speed bumps..... yet. It does hang lower than the engine cross member.



My front suspension is stock and it sits pretty low.

 

[Featherman]

Same Dilema

I too am in the same boat!! I have all the parts (new DTT) to rebuild my transmission, but I am a little reluctant to get a local shop to do the work. I have contacted DTT and they don't have 1st gen cores kicking around so, I either have to remove mine and let the truck sit for a few weeks or try to buy a core to ship out to DTT or drive out there to get the work done.



Needless to say, I haven't made a decision as to which way to go. Truth be known, if I could find a core I would rather go that route.



Excellent write up on the post though.

 

[Grey Wolf]

CHanstedt,



Although I don't have an automatic, I thought that this was the most complete and interesting write up I've seen in a long while. However I do have friends with Autos so we'll all be looking for your follow ups.



Good luck at the races and thanks for sharing, GW

 

[ESchoon]

Anymore comments or feedback after some towing with the transmission?



Looking at getting a new Auto for my 92 D350.

 

[Ggg]

I am anxiously awaiting any updates. I want to get my 727 rebuilt again. It has 480k and only one rebuild about 450k ago. I am looking at Goerend bros. Did you consider them as well as Suncoast?

 

[CHanstedt]

Still running strong

CHanstedt here-



So far I haven't towed anything other than an empty trailer, which doesn't count for anything. At the moment the truck is again up on blocks but this time I am replacing the Turbo with a HX-35. In the process I noticed the expansion plugs were leaking and the coolant hoses on the heat exchanger looked pretty soft. So it turned into a big project, but I should be up and running tonight and then I'll pick up the trailer/race car from the shop this weekend.



I am contemplating a write up on the turbo swap.



No issues at this point with the Suncoast transmission. No leaks and it still is firm on the shifting. I do have a few scuff marks on the pan, I think I need to get a lift to get the ride height higher.



I did not research Goerend bros. , but they have a good reputation with this group. I look forward to reading any 1st Gen transmission experiences.



Over-and-Out.

 

[Buffalo]

832,



I had ATS, in the Denver, CO. area, install one of their transmissions in my '91. 5 W-250. It works great! Much, much better than stock. However, it is costly but, I guess you get what you pay for.



Previously, I had a transmission guy raise the line pressure, which, didn't do too much.

Then, I had the stock TC removed & rebuilt with "more grab" installed. At idle, it had a lot of grab. Had to really stand on the brake pedal at stoplights, ot hold it down. Once you got rolling & towing, uphill, it did nothing as compared to the stock configuration.



I, seriously, considered the DTT set-up but, with my previous experience with fixing non-lock-up TC's, I decided to go with the Triple-lok from ATS. My thinking was that the only way to get all the power to the rear wheels was with a locking TC.



From what I understan, TC technology has improved quite a bit, in the last few years. My rebuilt TC didn't work well, at all. However, I've tread of people that have used TC's from the same company & are very happy. I think there was a learning curve regarding properly working TC's behind Cummins engines. My TC was part of the learning curve. Even my ATS Triple-lok works quite well before it locks-up. Much better than previous TC's.



CHanstedt,



VERY nice looking truck. Hope the new transmission works well for you. Suncoast has a good name.



Where are you in Phoenix? I'm on the NW side.



Joe F. (Buffalo)

 

[Mopar_Tim]

if anyone is looking for a 2wd core transmission there is one in the classifieds :-laf