140 Amp Cadillac Deville Alternator Swap Observations

Mods move this if you need. Thought it probably pertained more to 1st gen so put here.

Okay, have an upgraded audio system part way installed and wanted to upgrade the electrical. As with the 05 Camry we have, where I found a Highlander 130 amp swaps right in, I was searching for a low cost alternative for the Tacoma. Sorry, can't afford the $300 to $500+ for some of these fancy alternators.

Saw the 1995 Cadillac Deville 4.9 140 amp swap on another site. Looked pretty straight forward so went for it.

Ended up getting two alternators as got one through eBay for a 95 Deville 4.9, but came in with the body broken and fan bent due to ship. Finally was able to go to the wrecking yard and got a 1994 Deville Concours 4.6L alternator. Same 140 amp, same alternator, just has different clocking on the plugs on the back. This did not bother me as I didn't like the clocking on the 4.9 alternator either. Useable, but did not like where they came out. Guess my own preference there really.

Off we go with the swap.

 

Put this in a different box to break things up a bit.

Truck is a 1995 Tacoma xtra cab, 3.4L, Deluxe, manual transmission, 4wd

Here are just my observations. Only posting to at least prepare fellow TWer's who want to do the swap things that they "might" run into depending on the configuration of their truck/year. I only have my truck to go by which is as described above and was totally stock. Just posting as I did not find the swap as straight forward as listed.

First off, I did not like the way the plugs were oriented (clocked) on either the 4.9 or the 4.6 deville. Just seemed like might be too prone to heat from the exhaust and might be tough for me to get to. As such I used my old method of reclocking an alternator without having to deal with the internals. I took the pulley off the Cad alternator, took the 4 body bolts holding the two halves together out and gently pryed up on the front case to just lift it. This allowed me to spin the front part of the body around so the plugs were oriented the way I wanted. I then put the four bolts back in and reinstalled the pulley.

I now have the plug and battery connection vertical up and down and on the outside away from the engine.

Next thing was the space for the pivot mount. The Toyota pivot mount (wider of the two mounts) is bigger than the Cad one. In the write up the Cad alternator is listed as being 1/4 inch smaller so use a 1/4" spacer or a couple of 1/8 washers.

I measured my alternators with a digital caliper and found both alternators to vary in size to that listed by different amounts. I adjusted the measured washers to get the same thickness as the factory alternator for the Cad alternator I was installing. I'd suggest you measure your existing Toyota alternator and the Cad one and compare so you can get the correct spacer needed.

Next thing is the lower bolt. Be prepared that the factory threaded bolt that slides through from your adjuster is smaller than the hole in the Cad alternator. In a way this is good as the Cad alternators I have the hole is threaded and designed for a bolt to thread into. The Toyota adjusting bolt retainer being smaller in diameter allows it so slip through. Just believe it could be a potential for play in the system if care is not taken to ensure all aligned and tightened correctly.

Overall, alternator slipped in without too much bother. Loosened bottom alternator bracket bolt on the engine so it was out of the way. Started the pivot bolt and then aligned the bottom adjuster bracket and slipped the adjuster bolt through the alternator mount. No biggie.

Did remove the little heat/splash shield that is above the alternator towards the back. Just so I could see more. Reinstalled it once all bolted together. You don't need to do this, but I did.

To do install I did have to remove the factory skid plate as easier to get to some things from underneath the truck and get all tightened and aligned.

One of the biggest deals for me was the belt. According to the write up I looked at the factory belt could be reused. At least on my truck I found this not to be so.

This is the first Tacoma I've owned and worked on so I only have experience with my Tacoma and no others so don't know if all are built the same. On my truck the alternator would not adjust in enough for the stock belt to slip on. The larger Cad alternator body contacted the oil cooler hose and would not adjust any further in to allow the belt on the pulley.

My stock alternator belt was a NAPA 25-040413. Basically a 4 rib 41.3 long belt. After guessing too long with a 43.0 belt (ran out of adjustment on the adjusting arm trying to tighten). Ended up trying the power steering belt NAPA 25-040420 which is a 4 rib 42.0 belt and it worked fine. Was able to get the belt on and also adjust it tight with room to spare on the adjuster.

Plug wise for the new alternator I used a BWD PT200. Has three wires on it of which you just hook up two. The S pin to the battery peg on the back of the alternator and the L pin to the yellow wire in the truck's stock alternator harness. O'Reilly Autoparts listed having it to order, but found it at Pepboys in stock. They were higher on it, but price matched the lower O'Reilly price with an additional 5 percent off.

On the battery stud connection, the factory wire had two prongs off each side of the ring connector. These held the wire from twisting when you were tightening the connection on the factory alternator. I was concerned that these would cause an issue when mounting to the Cad alternator. Also the stud size is larger on the Cad alternator. I held the connector with some needle nose pliers and drilled out the hole to match the new stud size. I then took another pair of pliers and bent the tabs on either side back and forth until they snapped off. You may not need to do this. I just wanted a good connection with no potential problems.

Got it on, tested it and I'm at a low of 14.29 with A/C on max, lights on and system (no sub yet) jamming at idle. Bliss!

 

I re-used the stock belt. I have an 04 xtra cab 3.4 5 speed. The thing used to adjust the alternator, the thing where the alternator bolts to at the bottom, I undid the bolt and moved it down, this allowed me to be able to adjust the alternator farther in to be able to re-use the stock belt. Sorry, im not sure what that thing is called.

 

Thanks for posting. That is what I wanted to make people aware of. Some later models or perhaps different equipment can reuse the same belt it looks like. On my 95 there was no way. I had the bottom bracket like you, but the alternator body pivoted on the top mount pivot and contacted the oil cooler hose that is mounted right there long before it was in far enough to get the stock belt on.

Thanks for posting the alternators on eBay. I just had a hard time trusting them coming from the car audio world. You see so many budget alternators that actually end up putting out less power than the factory alternator at idle. I'm sure some are good and work, but a real crap shoot on who I felt comfortable trusting.

More importantly I guess, I'm as budget challenged and CHEAP as they come. So that's why I looked to an OE alternator conversion. I've got $45 total in the alt, plug and having to go buy another belt so that's more inline with the old pocket lol.

As a matter of interest while I was looking for alternatives I did contact the 130 amp seller. After numerous trys they finally responded with the output curve on the alternator. Engine idle rpm of 750-800 the alternator was rated at 30 amps output and only reached output of 130 amps when the engine was at 6,000 rpm. Calculating the power curve it would not provide what I needed. I did not contact the 170 amp one as by then I'd found the Cad alternator conversion write up AND of course I'm cheap lol.

Thanks for the posts all. Hope the info at least gives others something to think about and be potentially prepared for.

Would I do it again, right now I'd have to say yes. Rock solid power and cheap, readily available replacement at pretty much any autoparts store or wrecking yard when needed.

Cheers

 

This is what the 170A bolt in one says about it's power curve. I'm really impressed that it's a denso, it's great that you don't have to worry about it failing.

"***Full output of 170 Amps is achieved at 1200 engine rpm.***"

 

Looks like those numbers are pretty good from the 170amp seller. Sadly not all "HO" eBay alternators are as forth right and real world output numbers leave a lot to be desired. Just takes a scan of the car audio forums to confirm issues some are having with budget HO alternators.

Point of the post though was not to debate the merits of alternate alternator sources, but to provide potential info for others who are maybe going to go down the Cadillac alternator route and potential things they may run into so they can be prepared when doing the conversion.

For example, from what I found doing mine, to have a selection of spacer washers to get the correct spacing rather than just relying on 1/4" would have been useful. That way you can complete the install and get the belt aligned correctly. The potential need to purchase a belt and what size should work would have been great to know up front before starting my conversion also.

If I was one of the fortunate ones that the factory belt fit without issues then I could easily take the belt back and get my money back. If it was not, then I'd have the belt right there and be able to get the truck back up and running.

In my infinite, skin flint cheapness the GM CS144 alternator off of the Cadillac made the most sense and was the most budget friendly. Reliable proven solid 140amp power. A very budget friendly $45 in my total conversion. Replacements if needed readily available at the corner autoparts store or at the wrecker pretty much nation wide. Just my choice.

I just hoped that the post would help give insight to the conversion and maybe help others going down the same road to have a smoother time of it.

Was it an ordeal, no not really. Just a few items would have been good to be prepared for. Would I do it again, as I said, yes.

Thanks all for your interest and your posts.

Cheers

 

Wow, that's a lot of light power!!!

Yes, no super charger in the cards for me. Just needed the power upgrade for audio system. No winches or the like. The Cad at 140 should give me room to spare as not going over the top on this one.

Did not mention the upgraded wiring as thought that was a given, but yes. Ran 4g from the alternator output post, through a mini ANL fuse (6" from battery post) to the positive terminal on the battery. Then ran a 4g back through another mini ANL fuse back to the amps where it goes into a combo fuse block distrubution block. Kept all the stock positive connections as they were. Same with the ground side. Kept all the stock ground connections the same, but ran an additional 4g to the engine and another 4g to the body.

Hope that make sense.

Thanks again for the posts.
Cheers

 

Looks great!

My set up is a bit different and not really liking my mount for the fuses. Might do something similar and mount to the fender. I mounted mine using plexi to the relay block cover. Wanted to try and get as close to the battery connection as possible. As I said though, not really sure I like it there and how I have it mounted.

Sadly no pics as yet.

Did you upgrade your grounds as well?

Man, with that much light underneath, if you get some air over a hill you must look like a stealth fighter coming in for a landing!

 

All that light makes a mockery of cars now with their "puddle lamps"! Nice job!

Lightweight I am, all I've added in lighting is a 4Runner map light mirror and wired in some foot well courtesy lights as it was too dark for me inside the truck. Biggest thing for me now is to maybe find a decent way to get better headlamps on the 95 as the old style headlamps are pretty dim compared to newer vehicles. Not researched heavily yet on that though.

Ah, yes, see the ground now. With the light glinting off of it made it look smaller size wire on initial look.

 

I had my local alternator shop put a 130 amp stator in my factory unit and it puts out 150 amps im happy but it's doesn't put anything out at idle and i have a 2.1 pully on it.. kinda looking for an ho that charges at idle.. any ideas guys??

 

It's ok my Taco is worth it. im gonna have front and rear mount winch's and i just ordered my new audio system and lighting from hell.

 

Depends what power you need.

Further up in this post is the link for a 170amp. I've not worked with it, but the post says it is all in at 1200 rpm.

Alternatively there is the Cadillac alternator which is the subject of my original post. Keep in mind that you need to upgrade the electrical system. A bit of that has been discussed in the last few posts. Correct size wire and fuses etc. for the amperage you are carrying.

Just depends on what load you are going to put on the system/add to it. Might be best to post a new topic, explain exactly what you are running and want to do, give a budget and then perhaps more detailed info can be given. Cheers

EDIT: Looks like I'm way to slow and long winded as usual. Other posts popped in while I was typing mine. If you have the budget then the big name suppliers as previously posted can put something together for you I'm sure. Same thing applies to "system" though. Always think safety.

 

Pics?

 

This does a better job of showing pics on how to do the conversion. Basis for my making the swap. Hope it helps.